diff --git a/go/reg-test/expected/case-auxents.sh.err b/go/reg-test/expected/case-auxents.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-auxents.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-chaining.sh.err b/go/reg-test/expected/case-chaining.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-chaining.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-cli-help.sh.err b/go/reg-test/expected/case-cli-help.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-cli-help.sh.err
+++ b/go/reg-test/expected/case-cli-help.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-absent-empty.sh.err b/go/reg-test/expected/case-dsl-absent-empty.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-absent-empty.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-argpass-typedecl.sh.err b/go/reg-test/expected/case-dsl-argpass-typedecl.sh.err
new file mode 100644
index 000000000..78201ab84
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-argpass-typedecl.sh.err
@@ -0,0 +1,9 @@
+
+Miller: couldn't assign variable int i from value float 0.3467901443380824
+Miller: couldn't assign variable int function return value from value float 3.7967901443380825
+Miller: couldn't assign variable int function return value from value float 4.45
+Miller: couldn't assign variable int function return value from value error (error)
+Miller: couldn't assign variable int i from value float 0.3467901443380824
+
+Miller: couldn't assign variable num i from value string a
+
diff --git a/go/reg-test/expected/case-dsl-argpass-typedecl.sh.out b/go/reg-test/expected/case-dsl-argpass-typedecl.sh.out
index 3b9afd584..00563ecdd 100644
--- a/go/reg-test/expected/case-dsl-argpass-typedecl.sh.out
+++ b/go/reg-test/expected/case-dsl-argpass-typedecl.sh.out
@@ -22,7 +22,6 @@ mlr --from ./reg-test/input/abixy put
   }
   $c = f($x);
 
-mlr: int type assertion for variable i unmet by value 0.346790 with type float.
 
 mlr --from ./reg-test/input/abixy put 
   func f(num i): int {
@@ -30,7 +29,6 @@ mlr --from ./reg-test/input/abixy put
   }
   $c = f($x);
 
-mlr: function f returned type float, not matching typedecl int.
 
 mlr --from ./reg-test/input/abixy put 
   func f(num i): int {
@@ -38,7 +36,6 @@ mlr --from ./reg-test/input/abixy put
   }
   $c = f($i);
 
-mlr: function f returned type float, not matching typedecl int.
 
 mlr --from ./reg-test/input/abixy put 
   func f(num i): int {
@@ -47,7 +44,6 @@ mlr --from ./reg-test/input/abixy put
   }
   $c = f($x);
 
-mlr: numeric type assertion for variable i unmet by value "a" with type string.
 
 mlr --from ./reg-test/input/abixy put 
   subr s(int i) {
@@ -82,7 +78,6 @@ mlr --from ./reg-test/input/abixy put
   }
   call s($x);
 
-mlr: int type assertion for variable i unmet by value 0.346790 with type float.
 
 mlr --from ./reg-test/input/abixy put 
   subr s(num i) {
@@ -91,5 +86,4 @@ mlr --from ./reg-test/input/abixy put
   }
   call s($x);
 
-mlr: numeric type assertion for variable i unmet by value "a" with type string.
 
diff --git a/go/reg-test/expected/case-dsl-array-map-indexing.sh.err b/go/reg-test/expected/case-dsl-array-map-indexing.sh.err
index e69de29bb..2a89101d9 100644
--- a/go/reg-test/expected/case-dsl-array-map-indexing.sh.err
+++ b/go/reg-test/expected/case-dsl-array-map-indexing.sh.err
@@ -0,0 +1,8 @@
+
+Miller: '[[...]]' is allowed on assignment left-hand sides only when immediately preceded by '$'.
+Miller: '[[[...]]]' is allowed on assignment left-hand sides only when immediately preceded by '$'.
+Miller: '[[...]]' is allowed on assignment left-hand sides only when immediately preceded by '$'.
+Miller: '[[...]]' is allowed on assignment left-hand sides only when immediately preceded by '$'.
+Miller: '[[...]]' is allowed on assignment left-hand sides only when immediately preceded by '$'.
+Miller: '[[...]]' is allowed on assignment left-hand sides only when immediately preceded by '$'.
+Miller: '[[[...]]]' is allowed on assignment left-hand sides only when immediately preceded by '$'.
diff --git a/go/reg-test/expected/case-dsl-arrayify.sh.err b/go/reg-test/expected/case-dsl-arrayify.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-arrayify.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-asserting.sh.err b/go/reg-test/expected/case-dsl-asserting.sh.err
new file mode 100644
index 000000000..7640b4610
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-asserting.sh.err
@@ -0,0 +1,65 @@
+
+Miller: is_absent type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_absent type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_absent type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_absent type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_absent type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_absent type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_non_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_non_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_non_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_non_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_non_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_non_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_non_empty_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_not_empty type-assertion failed at NR=4 FNR=4 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_not_empty type-assertion failed at NR=3 FNR=3 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_not_empty type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_not_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_not_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_not_map type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_not_null type-assertion failed at NR=4 FNR=4 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_not_null type-assertion failed at NR=3 FNR=3 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_not_null type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_not_null type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_not_null type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_null type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_null type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_null type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_null type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_null type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_numeric type-assertion failed at NR=4 FNR=4 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_numeric type-assertion failed at NR=3 FNR=3 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_numeric type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_numeric type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_numeric type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_numeric type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_present type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_present type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_string type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_string type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_string type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_string type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
+Miller: is_string type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/nullvals.dkvp
diff --git a/go/reg-test/expected/case-dsl-basic.sh.err b/go/reg-test/expected/case-dsl-basic.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-basic.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-begin-end.sh.err b/go/reg-test/expected/case-dsl-begin-end.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-begin-end.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-block-exit.sh.err b/go/reg-test/expected/case-dsl-block-exit.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-block-exit.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-break-continue.sh.err b/go/reg-test/expected/case-dsl-break-continue.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-break-continue.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-clean-whitespace.sh.err b/go/reg-test/expected/case-dsl-clean-whitespace.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-clean-whitespace.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-collection-equality.sh.err b/go/reg-test/expected/case-dsl-collection-equality.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-collection-equality.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-comments.sh.err b/go/reg-test/expected/case-dsl-comments.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-comments.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-context-specific-validation.sh.err b/go/reg-test/expected/case-dsl-context-specific-validation.sh.err
new file mode 100644
index 000000000..21c0d4e4b
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-context-specific-validation.sh.err
@@ -0,0 +1,21 @@
+
+Miller: begin blocks can only be at top level.
+Miller: begin blocks can only be at top level.
+Miller: end blocks can only be at top level.
+Miller: end blocks can only be at top level.
+Miller: begin/end blocks cannot refer to records via $x, $*, etc.
+Miller: begin/end blocks cannot refer to records via $x, $*, etc.
+Miller: begin/end blocks cannot refer to records via $x, $*, etc.
+Miller: begin/end blocks cannot refer to records via $x, $*, etc.
+Miller: begin/end blocks cannot refer to records via $x, $*, etc.
+Miller: begin/end blocks cannot refer to records via $x, $*, etc.
+Miller: begin/end blocks cannot refer to records via $x, $*, etc.
+Miller: begin/end blocks cannot refer to records via $x, $*, etc.
+Miller: begin/end blocks cannot refer to records via $x, $*, etc.
+Miller: begin/end blocks cannot refer to records via $x, $*, etc.
+Miller: break statements are only valid within for/do/while loops.
+Miller: break statements are only valid within for/do/while loops.
+Miller: break statements are only valid within for/do/while loops.
+Miller: break statements are only valid within for/do/while loops.
+Miller: filter expressions must not also contain the "filter" keyword.
+Miller: filter expressions must not also contain the "filter" keyword.
diff --git a/go/reg-test/expected/case-dsl-context-validation.sh.err b/go/reg-test/expected/case-dsl-context-validation.sh.err
new file mode 100644
index 000000000..c356a9df8
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-context-validation.sh.err
@@ -0,0 +1,12 @@
+
+Miller: begin blocks can only be at top level.
+Miller: end blocks can only be at top level.
+Miller: begin blocks can only be at top level.
+Miller: end blocks can only be at top level.
+Miller: func blocks can only be at top level.
+Miller: begin/end blocks cannot refer to records via $x, $*, etc.
+Miller: return statements are only valid within func/subr blocks.
+Miller: break statements are only valid within for/do/while loops.
+Miller: break statements are only valid within for/do/while loops.
+Miller: break statements are only valid within for/do/while loops.
+Miller: break statements are only valid within for/do/while loops.
diff --git a/go/reg-test/expected/case-dsl-depth.sh.err b/go/reg-test/expected/case-dsl-depth.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-depth.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-do-while-loops.sh.err b/go/reg-test/expected/case-dsl-do-while-loops.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-do-while-loops.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-do-while.sh.err b/go/reg-test/expected/case-dsl-do-while.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-do-while.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-dump-print.sh.err b/go/reg-test/expected/case-dsl-dump-print.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-dump-print.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-emit-het.sh.err b/go/reg-test/expected/case-dsl-emit-het.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-emit-het.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-emit.sh.err b/go/reg-test/expected/case-dsl-emit.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-emit.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-empty-statements.sh.err b/go/reg-test/expected/case-dsl-empty-statements.sh.err
new file mode 100644
index 000000000..4f33636b9
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-empty-statements.sh.err
@@ -0,0 +1,2 @@
+
+Miller: filter statement must not be empty.
diff --git a/go/reg-test/expected/case-dsl-empty.sh.err b/go/reg-test/expected/case-dsl-empty.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-empty.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-env.sh.err b/go/reg-test/expected/case-dsl-env.sh.err
new file mode 100644
index 000000000..1ac68d175
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-env.sh.err
@@ -0,0 +1,2 @@
+
+Miller: ENV[...] cannot be indexed.
diff --git a/go/reg-test/expected/case-dsl-extended-typeof.sh.err b/go/reg-test/expected/case-dsl-extended-typeof.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-extended-typeof.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-filter.sh.err b/go/reg-test/expected/case-dsl-filter.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-filter.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-flatten-unflatten.sh.err b/go/reg-test/expected/case-dsl-flatten-unflatten.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-flatten-unflatten.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-for-bind-loops-for-valgrind.sh.err b/go/reg-test/expected/case-dsl-for-bind-loops-for-valgrind.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-for-bind-loops-for-valgrind.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-for-map-depth.sh.err b/go/reg-test/expected/case-dsl-for-map-depth.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-for-map-depth.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-for-multi.sh.err b/go/reg-test/expected/case-dsl-for-multi.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-for-multi.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-for-one.sh.err b/go/reg-test/expected/case-dsl-for-one.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-for-one.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-for-oosvar-loops.sh.err b/go/reg-test/expected/case-dsl-for-oosvar-loops.sh.err
new file mode 100644
index 000000000..49a81a2c7
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-for-oosvar-loops.sh.err
@@ -0,0 +1,12 @@
+
+mlr: redefinition of variable k in the same scope.
+mlr: redefinition of variable k in the same scope.
+mlr: redefinition of variable a in the same scope.
+mlr: redefinition of variable a in the same scope.
+mlr: redefinition of variable b in the same scope.
+mlr: redefinition of variable a in the same scope.
+mlr: redefinition of variable a in the same scope.
+mlr: redefinition of variable a in the same scope.
+mlr: redefinition of variable b in the same scope.
+mlr: redefinition of variable b in the same scope.
+mlr: redefinition of variable c in the same scope.
diff --git a/go/reg-test/expected/case-dsl-for-srec-loops.sh.err b/go/reg-test/expected/case-dsl-for-srec-loops.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-for-srec-loops.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-for-two.sh.err b/go/reg-test/expected/case-dsl-for-two.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-for-two.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-for-variants.sh.err b/go/reg-test/expected/case-dsl-for-variants.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-for-variants.sh.err
+++ b/go/reg-test/expected/case-dsl-for-variants.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-forbind-typedecl.sh.err b/go/reg-test/expected/case-dsl-forbind-typedecl.sh.err
new file mode 100644
index 000000000..21f573cf9
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-forbind-typedecl.sh.err
@@ -0,0 +1,7 @@
+
+Miller: couldn't assign variable float i from value int 0
+
+Miller: couldn't assign variable int i from value float 1.5
+
+Miller: couldn't assign variable int i from value float 1
+
diff --git a/go/reg-test/expected/case-dsl-from-file.sh.err b/go/reg-test/expected/case-dsl-from-file.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-from-file.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-func-decl-hoist.sh.err b/go/reg-test/expected/case-dsl-func-decl-hoist.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-func-decl-hoist.sh.err
+++ b/go/reg-test/expected/case-dsl-func-decl-hoist.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-functional-tests.sh.err b/go/reg-test/expected/case-dsl-functional-tests.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-functional-tests.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-hashing.sh.err b/go/reg-test/expected/case-dsl-hashing.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-hashing.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-haskey.sh.err b/go/reg-test/expected/case-dsl-haskey.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-haskey.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-if-chain.sh.err b/go/reg-test/expected/case-dsl-if-chain.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-if-chain.sh.err
+++ b/go/reg-test/expected/case-dsl-if-chain.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-if-chaining.sh.err b/go/reg-test/expected/case-dsl-if-chaining.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-if-chaining.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-indexing.sh.err b/go/reg-test/expected/case-dsl-indexing.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-indexing.sh.err
+++ b/go/reg-test/expected/case-dsl-indexing.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-indirect-srec-assignments.sh.err b/go/reg-test/expected/case-dsl-indirect-srec-assignments.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-indirect-srec-assignments.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-is-predicates.sh.err b/go/reg-test/expected/case-dsl-is-predicates.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-is-predicates.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-json-collection-output.sh.err b/go/reg-test/expected/case-dsl-json-collection-output.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-json-collection-output.sh.err
+++ b/go/reg-test/expected/case-dsl-json-collection-output.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-json-parse-json-stringify.sh.err b/go/reg-test/expected/case-dsl-json-parse-json-stringify.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-json-parse-json-stringify.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-leafcount.sh.err b/go/reg-test/expected/case-dsl-leafcount.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-leafcount.sh.err
+++ b/go/reg-test/expected/case-dsl-leafcount.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-length-depth-leafcount.sh.err b/go/reg-test/expected/case-dsl-length-depth-leafcount.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-length-depth-leafcount.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-length.sh.err b/go/reg-test/expected/case-dsl-length.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-length.sh.err
+++ b/go/reg-test/expected/case-dsl-length.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-lhs-indexing.sh.err b/go/reg-test/expected/case-dsl-lhs-indexing.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-lhs-indexing.sh.err
+++ b/go/reg-test/expected/case-dsl-lhs-indexing.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-local-map-variable-typedecl.sh.err b/go/reg-test/expected/case-dsl-local-map-variable-typedecl.sh.err
new file mode 100644
index 000000000..5d2966672
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-local-map-variable-typedecl.sh.err
@@ -0,0 +1,5 @@
+
+Miller: couldn't assign variable map a from value int 2
+
+Miller: couldn't assign variable map a from value int 2
+
diff --git a/go/reg-test/expected/case-dsl-local-map-variable-typedecl.sh.out b/go/reg-test/expected/case-dsl-local-map-variable-typedecl.sh.out
index 1bce9313b..d62326090 100644
--- a/go/reg-test/expected/case-dsl-local-map-variable-typedecl.sh.out
+++ b/go/reg-test/expected/case-dsl-local-map-variable-typedecl.sh.out
@@ -16,12 +16,10 @@ mlr --from ./reg-test/input/xyz345 put
     a=2;
     a[3][4]=5;
 
-mlr: map type assertion for variable a unmet by value 2 with type int.
 
 mlr --from ./reg-test/input/xyz345 put 
     map a = {};
     a[3][4]=5;
     a=2;
 
-mlr: map type assertion for variable a unmet by value 2 with type int.
 
diff --git a/go/reg-test/expected/case-dsl-local-map-variable-write-read.sh.err b/go/reg-test/expected/case-dsl-local-map-variable-write-read.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-local-map-variable-write-read.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-localvar-scope-and-extent.sh.err b/go/reg-test/expected/case-dsl-localvar-scope-and-extent.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-localvar-scope-and-extent.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-localvar-typedecl.sh.err b/go/reg-test/expected/case-dsl-localvar-typedecl.sh.err
new file mode 100644
index 000000000..bfea28db2
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-localvar-typedecl.sh.err
@@ -0,0 +1,5 @@
+
+Miller: couldn't assign variable str a from value int 1
+
+Miller: couldn't assign variable int a from value string pan
+
diff --git a/go/reg-test/expected/case-dsl-localvar-typedecl.sh.out b/go/reg-test/expected/case-dsl-localvar-typedecl.sh.out
index 37a7962b5..53f58d7a5 100644
--- a/go/reg-test/expected/case-dsl-localvar-typedecl.sh.out
+++ b/go/reg-test/expected/case-dsl-localvar-typedecl.sh.out
@@ -20,14 +20,12 @@ mlr --from ./reg-test/input/abixy put
   a = NR;
   $c = a;
 
-mlr: string type assertion for variable a unmet by value 1 with type int.
 
 mlr --from ./reg-test/input/abixy put 
   int a = $a;
   a = NR;
   $c = a;
 
-mlr: int type assertion for variable a unmet by value "pan" with type string.
 
 mlr --from ./reg-test/input/abixy put 
   int i = $i;
diff --git a/go/reg-test/expected/case-dsl-localvar-unsets.sh.err b/go/reg-test/expected/case-dsl-localvar-unsets.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-localvar-unsets.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-map-funcs.sh.err b/go/reg-test/expected/case-dsl-map-funcs.sh.err
index e69de29bb..b3f92b716 100644
--- a/go/reg-test/expected/case-dsl-map-funcs.sh.err
+++ b/go/reg-test/expected/case-dsl-map-funcs.sh.err
@@ -0,0 +1,5 @@
+
+Miller: function %!s(int=1) takes minimum argument count 0; got %!d(MISSING).
+
+Miller: function %!s(int=1) takes minimum argument count 0; got %!d(MISSING).
+
diff --git a/go/reg-test/expected/case-dsl-map-funcs.sh.out b/go/reg-test/expected/case-dsl-map-funcs.sh.out
index 4e19799b0..340aad390 100644
--- a/go/reg-test/expected/case-dsl-map-funcs.sh.out
+++ b/go/reg-test/expected/case-dsl-map-funcs.sh.out
@@ -24,10 +24,8 @@ mlr --from ./reg-test/input/abixy-het put -q o = mapdiff(); dump o
 {}
 
 mlr --from ./reg-test/input/abixy-het put -q o = mapexcept(); dump o
-Miller: couldn't assign variable var o from value error (error)
 
 mlr --from ./reg-test/input/abixy-het put -q o = mapselect(); dump o
-Miller: couldn't assign variable var o from value error (error)
 
 mlr --from ./reg-test/input/abixy-het put -q o = mapsum($*); dump o
 {
diff --git a/go/reg-test/expected/case-dsl-map-variant-dumps.sh.err b/go/reg-test/expected/case-dsl-map-variant-dumps.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-map-variant-dumps.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-mapsum-mapdiff-mapexcept.sh.err b/go/reg-test/expected/case-dsl-mapsum-mapdiff-mapexcept.sh.err
new file mode 100644
index 000000000..b3f92b716
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-mapsum-mapdiff-mapexcept.sh.err
@@ -0,0 +1,5 @@
+
+Miller: function %!s(int=1) takes minimum argument count 0; got %!d(MISSING).
+
+Miller: function %!s(int=1) takes minimum argument count 0; got %!d(MISSING).
+
diff --git a/go/reg-test/expected/case-dsl-mapsum-mapdiff-mapexcept.sh.out b/go/reg-test/expected/case-dsl-mapsum-mapdiff-mapexcept.sh.out
index 5ed1867d1..31ad90f28 100644
--- a/go/reg-test/expected/case-dsl-mapsum-mapdiff-mapexcept.sh.out
+++ b/go/reg-test/expected/case-dsl-mapsum-mapdiff-mapexcept.sh.out
@@ -24,10 +24,8 @@ mlr --from ./reg-test/input/abixy-het put -q o = mapdiff(); dump o
 {}
 
 mlr --from ./reg-test/input/abixy-het put -q o = mapexcept(); dump o
-Miller: couldn't assign variable var o from value error (error)
 
 mlr --from ./reg-test/input/abixy-het put -q o = mapselect(); dump o
-Miller: couldn't assign variable var o from value error (error)
 
 mlr --from ./reg-test/input/abixy-het put -q o = mapsum($*); dump o
 {
diff --git a/go/reg-test/expected/case-dsl-mapvar-assignments.sh.err b/go/reg-test/expected/case-dsl-mapvar-assignments.sh.err
new file mode 100644
index 000000000..0e6638202
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-mapvar-assignments.sh.err
@@ -0,0 +1,11 @@
+
+Cannot assign non-map to existing map; got int.
+Cannot assign non-map to existing map; got int.
+Cannot assign non-map to existing map; got int.
+Cannot assign non-map to existing map; got int.
+Cannot assign non-map to existing map; got int.
+Cannot assign non-map to existing map; got int.
+Miller: couldn't assign variable map o from value int 1
+
+Miller: couldn't assign variable map o from value int 1
+
diff --git a/go/reg-test/expected/case-dsl-mapvar-emit.sh.err b/go/reg-test/expected/case-dsl-mapvar-emit.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-mapvar-emit.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-mapvar-for-loops.sh.err b/go/reg-test/expected/case-dsl-mapvar-for-loops.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-mapvar-for-loops.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-mapvars-in-scalar-function-call-contexts.sh.err b/go/reg-test/expected/case-dsl-mapvars-in-scalar-function-call-contexts.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-mapvars-in-scalar-function-call-contexts.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-mapvars-udfs-subroutines.sh.err b/go/reg-test/expected/case-dsl-mapvars-udfs-subroutines.sh.err
new file mode 100644
index 000000000..cb5378802
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-mapvars-udfs-subroutines.sh.err
@@ -0,0 +1,7 @@
+
+Miller: couldn't assign variable int x from value float 0.3467901443380824
+Miller: couldn't assign variable int x from value float 0.3467901443380824
+Miller: couldn't assign variable int x from value float 0.3467901443380824
+Miller: couldn't assign variable int function return value from value absent (absent)
+Miller: couldn't assign variable var b from value error (error)
+
diff --git a/go/reg-test/expected/case-dsl-mathy.sh.err b/go/reg-test/expected/case-dsl-mathy.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-mathy.sh.err
+++ b/go/reg-test/expected/case-dsl-mathy.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-max-variadic.sh.err b/go/reg-test/expected/case-dsl-max-variadic.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-max-variadic.sh.err
+++ b/go/reg-test/expected/case-dsl-max-variadic.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-min-max-types.sh.err b/go/reg-test/expected/case-dsl-min-max-types.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-min-max-types.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-modular-arithmetic.sh.err b/go/reg-test/expected/case-dsl-modular-arithmetic.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-modular-arithmetic.sh.err
+++ b/go/reg-test/expected/case-dsl-modular-arithmetic.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-more-type-predicates.sh.err b/go/reg-test/expected/case-dsl-more-type-predicates.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-more-type-predicates.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-multi-index.sh.err b/go/reg-test/expected/case-dsl-multi-index.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-multi-index.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-multipart-scripts.sh.err b/go/reg-test/expected/case-dsl-multipart-scripts.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-multipart-scripts.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-nested-double-quotes.sh.err b/go/reg-test/expected/case-dsl-nested-double-quotes.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-nested-double-quotes.sh.err
+++ b/go/reg-test/expected/case-dsl-nested-double-quotes.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-no-filter-in-filter.sh.err b/go/reg-test/expected/case-dsl-no-filter-in-filter.sh.err
new file mode 100644
index 000000000..e796a0698
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-no-filter-in-filter.sh.err
@@ -0,0 +1,2 @@
+
+Miller: filter expressions must not also contain the "filter" keyword.
diff --git a/go/reg-test/expected/case-dsl-null-empty-handling.sh.err b/go/reg-test/expected/case-dsl-null-empty-handling.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-null-empty-handling.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-number-formatting.sh.err b/go/reg-test/expected/case-dsl-number-formatting.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-number-formatting.sh.err
+++ b/go/reg-test/expected/case-dsl-number-formatting.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-oosvar-assignments.sh.err b/go/reg-test/expected/case-dsl-oosvar-assignments.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-oosvar-assignments.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-oosvars.sh.err b/go/reg-test/expected/case-dsl-oosvars.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-oosvars.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-operator-associativity.sh.err b/go/reg-test/expected/case-dsl-operator-associativity.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-operator-associativity.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-operator-precedence.sh.err b/go/reg-test/expected/case-dsl-operator-precedence.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-operator-precedence.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-operator-rewrites.sh.err b/go/reg-test/expected/case-dsl-operator-rewrites.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-operator-rewrites.sh.err
+++ b/go/reg-test/expected/case-dsl-operator-rewrites.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-output-redirects.sh.err b/go/reg-test/expected/case-dsl-output-redirects.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-output-redirects.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-output-redirects.sh.out b/go/reg-test/expected/case-dsl-output-redirects.sh.out
index 4c7501fd7..2ef994110 100644
--- a/go/reg-test/expected/case-dsl-output-redirects.sh.out
+++ b/go/reg-test/expected/case-dsl-output-redirects.sh.out
@@ -4,7 +4,6 @@
 mlr --from ./reg-test/input/2.dkvp put @x=1; print
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; print
 
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 
@@ -15,7 +14,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; print > stdout
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; print > stdout
 
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 
@@ -26,7 +24,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; print > stderr
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; print > stderr
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -37,7 +34,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; print > ENV["outdir"]."/foo.dat"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; print > ENV["outdir"]."/foo.dat"
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -50,7 +46,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; print @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; print @x
 1
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 1
@@ -61,7 +56,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; print > stdout, @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; print > stdout, @x
 1
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 1
@@ -72,7 +66,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; print > stderr, @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; print > stderr, @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -83,7 +76,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; print > ENV["outdir"]."/foo.dat", @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; print > ENV["outdir"]."/foo.dat", @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -98,7 +90,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; printn
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; printn
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -107,7 +98,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; printn > stdout
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; printn > stdout
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -116,7 +106,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; printn > stderr
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; printn > stderr
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -125,7 +114,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; printn > ENV["outdir"]."/foo.dat"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; printn > ENV["outdir"]."/foo.dat"
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -136,7 +124,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; printn @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; printn @x
 1a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 1a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -145,7 +132,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; printn > stdout, @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; printn > stdout, @x
 1a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 1a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -154,7 +140,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; printn > stderr, @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; printn > stderr, @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -163,7 +148,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; printn > ENV["outdir"]."/foo.dat", @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; printn > ENV["outdir"]."/foo.dat", @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -176,7 +160,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; eprint
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; eprint
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -187,7 +170,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; eprint @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; eprint @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -200,7 +182,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; eprintn
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; eprintn
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -209,7 +190,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; eprintn @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; eprintn @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -220,7 +200,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; dump
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; dump
 {
   "x": 1
 }
@@ -235,7 +214,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; dump > stdout
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; dump > stdout
 {
   "x": 1
 }
@@ -250,7 +228,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; dump > stderr
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; dump > stderr
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -265,7 +242,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; dump > ENV["outdir"]."/foo.dat"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; dump > ENV["outdir"]."/foo.dat"
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -282,7 +258,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; dump @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; dump @x
 1
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 1
@@ -293,7 +268,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; dump > stdout, @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; dump > stdout, @x
 1
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 1
@@ -304,7 +278,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; dump > stderr, @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; dump > stderr, @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -315,7 +288,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; dump > ENV["outdir"]."/foo.dat", @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; dump > ENV["outdir"]."/foo.dat", @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -330,7 +302,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; edump
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; edump
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -345,7 +316,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; edump @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; edump @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -358,7 +328,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put -q @x=1; tee > stdout, $*
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put -q @x=1; tee > stdout, $*
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -367,7 +336,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; tee > stderr, $*
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; tee > stderr, $*
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -378,7 +346,6 @@ a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 mlr --from ./reg-test/input/2.dkvp put @x=1; tee > ENV["outdir"]."/foo.dat", $*
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; tee > ENV["outdir"]."/foo.dat", $*
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -393,7 +360,6 @@ a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 mlr --from ./reg-test/input/2.dkvp put @x=1; emitf @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; emitf @x
 x=1
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 x=1
@@ -404,7 +370,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put -q @x=1; emitf > stdout, @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put -q @x=1; emitf > stdout, @x
 x=1
 x=1
 
@@ -413,7 +378,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; emitf > stderr, @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; emitf > stderr, @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -424,7 +388,6 @@ x=1
 mlr --from ./reg-test/input/2.dkvp put @x=1; emitf > ENV["outdir"]."/foo.dat", @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; emitf > ENV["outdir"]."/foo.dat", @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -439,7 +402,6 @@ x=1
 mlr --from ./reg-test/input/2.dkvp put @x=1; emit @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; emit @x
 x=1
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 x=1
@@ -450,7 +412,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put -q @x=1; emit > stdout, @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put -q @x=1; emit > stdout, @x
 x=1
 x=1
 
@@ -459,7 +420,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; emit > stderr, @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; emit > stderr, @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -470,7 +430,6 @@ x=1
 mlr --from ./reg-test/input/2.dkvp put @x=1; emit > ENV["outdir"]."/foo.dat", @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; emit > ENV["outdir"]."/foo.dat", @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -483,7 +442,6 @@ x=1
 mlr --from ./reg-test/input/2.dkvp put @x=1; @y=2; emit (@x, @y)
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; @y=2; emit (@x, @y)
 x=1,y=2
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 x=1,y=2
@@ -494,7 +452,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put -q @x=1; @y=2; emit > stdout, (@x, @y)
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put -q @x=1; @y=2; emit > stdout, (@x, @y)
 x=1,y=2
 x=1,y=2
 
@@ -503,7 +460,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; @y=2; emit > stderr, (@x, @y)
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; @y=2; emit > stderr, (@x, @y)
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -514,7 +470,6 @@ x=1,y=2
 mlr --from ./reg-test/input/2.dkvp put @x=1; @y=2; emit > ENV["outdir"]."/foo.dat", (@x, @y)
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; @y=2; emit > ENV["outdir"]."/foo.dat", (@x, @y)
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -527,7 +482,6 @@ x=1,y=2
 mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; emit @x, "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; emit @x, "a"
 a=a,x=1
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=a,x=1
@@ -538,7 +492,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put -q @x={"a":1}; emit > stdout, @x, "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put -q @x={"a":1}; emit > stdout, @x, "a"
 a=a,x=1
 a=a,x=1
 
@@ -547,7 +500,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; emit > stderr, @x, "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; emit > stderr, @x, "a"
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -558,7 +510,6 @@ a=a,x=1
 mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; emit > ENV["outdir"]."/foo.dat", @x, "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; emit > ENV["outdir"]."/foo.dat", @x, "a"
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -571,7 +522,6 @@ a=a,x=1
 mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; @y={"a":2}; emit (@x, @y), "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; @y={"a":2}; emit (@x, @y), "a"
 a=a,x=1,y=2
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=a,x=1,y=2
@@ -582,7 +532,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put -q @x={"a":1}; @y={"a":2}; emit > stdout, (@x, @y), "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put -q @x={"a":1}; @y={"a":2}; emit > stdout, (@x, @y), "a"
 a=a,x=1,y=2
 a=a,x=1,y=2
 
@@ -591,7 +540,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; @y={"a":2}; emit > stderr, (@x, @y), "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; @y={"a":2}; emit > stderr, (@x, @y), "a"
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -602,7 +550,6 @@ a=a,x=1,y=2
 mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; @y={"a":2}; emit > ENV["outdir"]."/foo.dat", (@x, @y), "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; @y={"a":2}; emit > ENV["outdir"]."/foo.dat", (@x, @y), "a"
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -617,7 +564,6 @@ a=a,x=1,y=2
 mlr --from ./reg-test/input/2.dkvp put @x=1; emitp @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; emitp @x
 x=1
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 x=1
@@ -628,7 +574,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put -q @x=1; emitp > stdout, @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put -q @x=1; emitp > stdout, @x
 x=1
 x=1
 
@@ -637,7 +582,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; emitp > stderr, @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; emitp > stderr, @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -648,7 +592,6 @@ x=1
 mlr --from ./reg-test/input/2.dkvp put @x=1; emitp > ENV["outdir"]."/foo.dat", @x
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; emitp > ENV["outdir"]."/foo.dat", @x
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -661,7 +604,6 @@ x=1
 mlr --from ./reg-test/input/2.dkvp put @x=1; @y=2; emitp (@x, @y)
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; @y=2; emitp (@x, @y)
 x=1,y=2
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 x=1,y=2
@@ -672,7 +614,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put -q @x=1; @y=2; emitp > stdout, (@x, @y)
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put -q @x=1; @y=2; emitp > stdout, (@x, @y)
 x=1,y=2
 x=1,y=2
 
@@ -681,7 +622,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x=1; @y=2; emitp > stderr, (@x, @y)
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; @y=2; emitp > stderr, (@x, @y)
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -692,7 +632,6 @@ x=1,y=2
 mlr --from ./reg-test/input/2.dkvp put @x=1; @y=2; emitp > ENV["outdir"]."/foo.dat", (@x, @y)
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x=1; @y=2; emitp > ENV["outdir"]."/foo.dat", (@x, @y)
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -705,7 +644,6 @@ x=1,y=2
 mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; emitp @x, "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; emitp @x, "a"
 a=a,x=1
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=a,x=1
@@ -716,7 +654,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put -q @x={"a":1}; emitp > stdout, @x, "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put -q @x={"a":1}; emitp > stdout, @x, "a"
 a=a,x=1
 a=a,x=1
 
@@ -725,7 +662,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; emitp > stderr, @x, "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; emitp > stderr, @x, "a"
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -736,7 +672,6 @@ a=a,x=1
 mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; emitp > ENV["outdir"]."/foo.dat", @x, "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; emitp > ENV["outdir"]."/foo.dat", @x, "a"
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -749,7 +684,6 @@ a=a,x=1
 mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; @y={"a":2}; emitp (@x, @y), "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; @y={"a":2}; emitp (@x, @y), "a"
 a=a,x=1,y=2
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=a,x=1,y=2
@@ -760,7 +694,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put -q @x={"a":1}; @y={"a":2}; emitp > stdout, (@x, @y), "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put -q @x={"a":1}; @y={"a":2}; emitp > stdout, (@x, @y), "a"
 a=a,x=1,y=2
 a=a,x=1,y=2
 
@@ -769,7 +702,6 @@ cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test
 mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; @y={"a":2}; emitp > stderr, (@x, @y), "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; @y={"a":2}; emitp > stderr, (@x, @y), "a"
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
@@ -780,7 +712,6 @@ a=a,x=1,y=2
 mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; @y={"a":2}; emitp > ENV["outdir"]."/foo.dat", (@x, @y), "a"
 
 cat /Users/kerl/pub_http_internet/miller-releases/miller-head/go/output-reg-test/redirect-out.txt
-mlr --from ./reg-test/input/2.dkvp put @x={"a":1}; @y={"a":2}; emitp > ENV["outdir"]."/foo.dat", (@x, @y), "a"
 a=pan,b=pan,i=1,x=0.3467901443380824,y=0.7268028627434533
 a=eks,b=pan,i=2,x=0.7586799647899636,y=0.5221511083334797
 
diff --git a/go/reg-test/expected/case-dsl-parse.sh.err b/go/reg-test/expected/case-dsl-parse.sh.err
index e69de29bb..deb519b2c 100644
--- a/go/reg-test/expected/case-dsl-parse.sh.err
+++ b/go/reg-test/expected/case-dsl-parse.sh.err
@@ -0,0 +1,23 @@
+
+Miller: int literal is not valid for unset statement.
+mlr: cannot parse DSL expression.
+Parse error on token "`" at line 20 columnn 3.
+Please check for missing semicolon.
+Expected one of:
+  ; { } unset filter print printn eprint eprintn dump edump tee emitf emit
+  ( emitp field_name $[ braced_field_name $[[ $[[[ full_srec oosvar_name @[
+  braced_oosvar_name full_oosvar all non_sigil_name arr bool float int map
+  num str var + - .+ .- ! ~ string_literal regex_case_insensitive int_literal
+  float_literal boolean_literal const_M_PI const_M_E panic [ ctx_IPS ctx_IFS
+  ctx_IRS ctx_OPS ctx_OFS ctx_ORS ctx_OFLATSEP ctx_NF ctx_NR ctx_FNR ctx_FILENAME
+  ctx_FILENUM env call begin end if while do for break continue func subr
+  return
+
+mlr: cannot parse DSL expression.
+Parse error on token "x" at line 20 columnn 5.
+Please check for missing semicolon.
+Expected one of:
+  ; { } = > >> | ( ||= ^^= &&= ??= ???= |= &= ^= <<= >>= >>>= += .= -= *=
+  /= //= %= **= ? || ^^ && ?? ??? =~ !=~ == != >= < <= ^ & << >>> + - .+ .-
+  . * / // % .* ./ .// ** [ [[ [[[
+
diff --git a/go/reg-test/expected/case-dsl-print.sh.err b/go/reg-test/expected/case-dsl-print.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-print.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-programming-examples.sh.err b/go/reg-test/expected/case-dsl-programming-examples.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-programming-examples.sh.err
+++ b/go/reg-test/expected/case-dsl-programming-examples.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-put-dash-e-dash-f.sh.err b/go/reg-test/expected/case-dsl-put-dash-e-dash-f.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-put-dash-e-dash-f.sh.err
+++ b/go/reg-test/expected/case-dsl-put-dash-e-dash-f.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-put-dash-s.sh.err b/go/reg-test/expected/case-dsl-put-dash-s.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-put-dash-s.sh.err
+++ b/go/reg-test/expected/case-dsl-put-dash-s.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-pythonic-division.sh.err b/go/reg-test/expected/case-dsl-pythonic-division.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-pythonic-division.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-regex-matching.sh.err b/go/reg-test/expected/case-dsl-regex-matching.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-regex-matching.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-regex.sh.err b/go/reg-test/expected/case-dsl-regex.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-regex.sh.err
+++ b/go/reg-test/expected/case-dsl-regex.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-scientific-notation.sh.err b/go/reg-test/expected/case-dsl-scientific-notation.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-scientific-notation.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-scope.sh.err b/go/reg-test/expected/case-dsl-scope.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-scope.sh.err
+++ b/go/reg-test/expected/case-dsl-scope.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-sec2gmt.sh.err b/go/reg-test/expected/case-dsl-sec2gmt.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-sec2gmt.sh.err
+++ b/go/reg-test/expected/case-dsl-sec2gmt.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-semicolons.sh.err b/go/reg-test/expected/case-dsl-semicolons.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-semicolons.sh.err
+++ b/go/reg-test/expected/case-dsl-semicolons.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-short-circuit.sh.err b/go/reg-test/expected/case-dsl-short-circuit.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-short-circuit.sh.err
+++ b/go/reg-test/expected/case-dsl-short-circuit.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-slice.sh.err b/go/reg-test/expected/case-dsl-slice.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-slice.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-split-join-more.sh.err b/go/reg-test/expected/case-dsl-split-join-more.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-split-join-more.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-split-join.sh.err b/go/reg-test/expected/case-dsl-split-join.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-split-join.sh.err
+++ b/go/reg-test/expected/case-dsl-split-join.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-stack-allocation.sh.err b/go/reg-test/expected/case-dsl-stack-allocation.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-stack-allocation.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-strlen.sh.err b/go/reg-test/expected/case-dsl-strlen.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-strlen.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-subr.sh.err b/go/reg-test/expected/case-dsl-subr.sh.err
new file mode 100644
index 000000000..188665418
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-subr.sh.err
@@ -0,0 +1,16 @@
+
+Miller: subroutine name not found: s
+mlr: cannot parse DSL expression.
+Parse error on token "" at line 1 columnn 7.
+Expected one of:
+  (
+
+Miller: subroutine name not found: s
+Miller: return statements in subr blocks must not return a value.
+mlr: cannot parse DSL expression.
+Parse error on token "" at line 1 columnn 9.
+Expected one of:
+  {
+
+Miller: subroutine name not found: s
+Miller: subroutine named "s" has already been defined.
diff --git a/go/reg-test/expected/case-dsl-subs.sh.err b/go/reg-test/expected/case-dsl-subs.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-subs.sh.err
+++ b/go/reg-test/expected/case-dsl-subs.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-substr.sh.err b/go/reg-test/expected/case-dsl-substr.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-substr.sh.err
+++ b/go/reg-test/expected/case-dsl-substr.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-toupper-tolower.sh.err b/go/reg-test/expected/case-dsl-toupper-tolower.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-toupper-tolower.sh.err
+++ b/go/reg-test/expected/case-dsl-toupper-tolower.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-trailing-commas.sh.err b/go/reg-test/expected/case-dsl-trailing-commas.sh.err
new file mode 100644
index 000000000..3a669fe08
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-trailing-commas.sh.err
@@ -0,0 +1,57 @@
+
+mlr: cannot parse DSL expression.
+Parse error on token "," at line 1 columnn 35.
+Expected one of:
+  { ( ) field_name $[ braced_field_name $[[ $[[[ full_srec oosvar_name @[
+  braced_oosvar_name full_oosvar all non_sigil_name float int + - .+ .- !
+  ~ string_literal regex_case_insensitive int_literal float_literal boolean_literal
+  const_M_PI const_M_E panic [ ctx_IPS ctx_IFS ctx_IRS ctx_OPS ctx_OFS ctx_ORS
+  ctx_OFLATSEP ctx_NF ctx_NR ctx_FNR ctx_FILENAME ctx_FILENUM env
+
+mlr: cannot parse DSL expression.
+Parse error on token "," at line 1 columnn 10.
+Expected one of:
+  ) non_sigil_name arr bool float int map num str var
+
+mlr: cannot parse DSL expression.
+Parse error on token "," at line 1 columnn 14.
+Expected one of:
+  ) non_sigil_name arr bool float int map num str var
+
+mlr: cannot parse DSL expression.
+Parse error on token "," at line 1 columnn 37.
+Expected one of:
+  { ( ) field_name $[ braced_field_name $[[ $[[[ full_srec oosvar_name @[
+  braced_oosvar_name full_oosvar all non_sigil_name float int + - .+ .- !
+  ~ string_literal regex_case_insensitive int_literal float_literal boolean_literal
+  const_M_PI const_M_E panic [ ctx_IPS ctx_IFS ctx_IRS ctx_OPS ctx_OFS ctx_ORS
+  ctx_OFLATSEP ctx_NF ctx_NR ctx_FNR ctx_FILENAME ctx_FILENUM env
+
+mlr: cannot parse DSL expression.
+Parse error on token "," at line 1 columnn 10.
+Expected one of:
+  ) non_sigil_name arr bool float int map num str var
+
+mlr: cannot parse DSL expression.
+Parse error on token "," at line 1 columnn 14.
+Expected one of:
+  ) non_sigil_name arr bool float int map num str var
+
+mlr: cannot parse DSL expression.
+Parse error on token "," at line 1 columnn 13.
+Expected one of:
+  { ( ) field_name $[ braced_field_name $[[ $[[[ full_srec oosvar_name @[
+  braced_oosvar_name full_oosvar all non_sigil_name float int + - .+ .- !
+  ~ string_literal regex_case_insensitive int_literal float_literal boolean_literal
+  const_M_PI const_M_E panic [ ctx_IPS ctx_IFS ctx_IRS ctx_OPS ctx_OFS ctx_ORS
+  ctx_OFLATSEP ctx_NF ctx_NR ctx_FNR ctx_FILENAME ctx_FILENUM env
+
+mlr: cannot parse DSL expression.
+Parse error on token "," at line 1 columnn 10.
+Expected one of:
+  { ( ) field_name $[ braced_field_name $[[ $[[[ full_srec oosvar_name @[
+  braced_oosvar_name full_oosvar all non_sigil_name float int + - .+ .- !
+  ~ string_literal regex_case_insensitive int_literal float_literal boolean_literal
+  const_M_PI const_M_E panic [ ctx_IPS ctx_IFS ctx_IRS ctx_OPS ctx_OFS ctx_ORS
+  ctx_OFLATSEP ctx_NF ctx_NR ctx_FNR ctx_FILENAME ctx_FILENUM env
+
diff --git a/go/reg-test/expected/case-dsl-truncate.sh.err b/go/reg-test/expected/case-dsl-truncate.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-truncate.sh.err
+++ b/go/reg-test/expected/case-dsl-truncate.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-type-inference.sh.err b/go/reg-test/expected/case-dsl-type-inference.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-type-inference.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-type-predicates.sh.err b/go/reg-test/expected/case-dsl-type-predicates.sh.err
index e69de29bb..1be632e3a 100644
--- a/go/reg-test/expected/case-dsl-type-predicates.sh.err
+++ b/go/reg-test/expected/case-dsl-type-predicates.sh.err
@@ -0,0 +1,3 @@
+
+Miller: is_absent type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/s.dkvp
+Miller: is_empty type-assertion failed at NR=1 FNR=1 FILENAME=./reg-test/input/s.dkvp
diff --git a/go/reg-test/expected/case-dsl-type-reflect.sh.err b/go/reg-test/expected/case-dsl-type-reflect.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-type-reflect.sh.err
+++ b/go/reg-test/expected/case-dsl-type-reflect.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-typed-overlay.sh.err b/go/reg-test/expected/case-dsl-typed-overlay.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-typed-overlay.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-typedecl.sh.err b/go/reg-test/expected/case-dsl-typedecl.sh.err
index e69de29bb..f8ea9d8e9 100644
--- a/go/reg-test/expected/case-dsl-typedecl.sh.err
+++ b/go/reg-test/expected/case-dsl-typedecl.sh.err
@@ -0,0 +1,9 @@
+
+Miller: couldn't assign variable str x from value int 3
+
+Miller: couldn't assign variable arr x from value int 3
+
+Miller: couldn't assign variable str x from value int 3
+Miller: couldn't assign variable arr x from value int 3
+Miller: couldn't assign variable str function return value from value int 6
+Miller: couldn't assign variable arr function return value from value int 6
diff --git a/go/reg-test/expected/case-dsl-typedecl.sh.out b/go/reg-test/expected/case-dsl-typedecl.sh.out
index 17848bd64..df818a855 100644
--- a/go/reg-test/expected/case-dsl-typedecl.sh.out
+++ b/go/reg-test/expected/case-dsl-typedecl.sh.out
@@ -18,10 +18,8 @@ a=wye,b=wye,i=3,x=0.20460330576630303,y=0.33831852551664776
 a=eks,b=wye,i=4,x=0.38139939387114097,y=0.13418874328430463
 
 mlr --from ./reg-test/input/s.dkvp put str x = 3
-Miller: couldn't assign variable str x from value int 3
 
 mlr --from ./reg-test/input/s.dkvp put arr x = 3
-Miller: couldn't assign variable arr x from value int 3
 
 mlr --from ./reg-test/input/s.dkvp put func f(var x) { return 2*x} $y=f(3)
 a=pan,b=pan,i=1,x=0.3467901443380824,y=6
@@ -42,10 +40,8 @@ a=wye,b=wye,i=3,x=0.20460330576630303,y=6
 a=eks,b=wye,i=4,x=0.38139939387114097,y=6
 
 mlr --from ./reg-test/input/s.dkvp put func f(str x) { return 2*x} $y=f(3)
-Miller: couldn't assign variable str x from value int 3
 
 mlr --from ./reg-test/input/s.dkvp put func f(arr x) { return 2*x} $y=f(3)
-Miller: couldn't assign variable arr x from value int 3
 
 mlr --from ./reg-test/input/s.dkvp put func f(x): var { return 2*x} $y=f(3)
 a=pan,b=pan,i=1,x=0.3467901443380824,y=6
@@ -66,8 +62,6 @@ a=wye,b=wye,i=3,x=0.20460330576630303,y=6
 a=eks,b=wye,i=4,x=0.38139939387114097,y=6
 
 mlr --from ./reg-test/input/s.dkvp put func f(x): str { return 2*x} $y=f(3)
-Miller: couldn't assign variable str function return value from value int 6
 
 mlr --from ./reg-test/input/s.dkvp put func f(x): arr { return 2*x} $y=f(3)
-Miller: couldn't assign variable arr function return value from value int 6
 
diff --git a/go/reg-test/expected/case-dsl-unset.sh.err b/go/reg-test/expected/case-dsl-unset.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-unset.sh.err
+++ b/go/reg-test/expected/case-dsl-unset.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-user-defined-functions-and-subroutines.sh.err b/go/reg-test/expected/case-dsl-user-defined-functions-and-subroutines.sh.err
new file mode 100644
index 000000000..0772a0289
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-user-defined-functions-and-subroutines.sh.err
@@ -0,0 +1,24 @@
+
+Miller: return statements in subr blocks must not return a value.
+Miller: return statements in func blocks must return a value.
+Miller: function named "log" must not override a built-in function of the same name.
+Miller: begin blocks can only be at top level.
+Miller: end blocks can only be at top level.
+Miller: begin blocks can only be at top level.
+Miller: end blocks can only be at top level.
+Miller: func blocks can only be at top level.
+Miller: subr blocks can only be at top level.
+Miller: func blocks can only be at top level.
+Miller: subr blocks can only be at top level.
+Miller: begin blocks can only be at top level.
+Miller: end blocks can only be at top level.
+Miller: begin blocks can only be at top level.
+Miller: end blocks can only be at top level.
+Miller: func blocks can only be at top level.
+Miller: subr blocks can only be at top level.
+Miller: func blocks can only be at top level.
+Miller: subr blocks can only be at top level.
+Miller: function named "log" must not override a built-in function of the same name.
+Miller: function named "f" has already been defined.
+Miller: subroutine named "s" has already been defined.
+Miller: subroutine named "s" has already been defined.
diff --git a/go/reg-test/expected/case-dsl-user-defined-functions.sh.err b/go/reg-test/expected/case-dsl-user-defined-functions.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-user-defined-functions.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-utf8-strlen.sh.err b/go/reg-test/expected/case-dsl-utf8-strlen.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-utf8-strlen.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-utf8-uppercase-lowercase.sh.err b/go/reg-test/expected/case-dsl-utf8-uppercase-lowercase.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-utf8-uppercase-lowercase.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-warnings.sh.err b/go/reg-test/expected/case-dsl-warnings.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-dsl-warnings.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-dsl-whitespace.sh.err b/go/reg-test/expected/case-dsl-whitespace.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-dsl-whitespace.sh.err
+++ b/go/reg-test/expected/case-dsl-whitespace.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-io-barred-pprint.sh.err b/go/reg-test/expected/case-io-barred-pprint.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-io-barred-pprint.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-io-het-csv-input.sh.err b/go/reg-test/expected/case-io-het-csv-input.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-io-het-csv-input.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-io-json-io.sh.err b/go/reg-test/expected/case-io-json-io.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-io-json-io.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-io-multi.sh.err b/go/reg-test/expected/case-io-multi.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-io-multi.sh.err
+++ b/go/reg-test/expected/case-io-multi.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-io-ragged-non-rfc-csv.sh.err b/go/reg-test/expected/case-io-ragged-non-rfc-csv.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-io-ragged-non-rfc-csv.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-repl.sh.err b/go/reg-test/expected/case-repl.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-repl.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-altkv.sh.err b/go/reg-test/expected/case-verb-altkv.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-altkv.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-bootstrap.sh.err b/go/reg-test/expected/case-verb-bootstrap.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-bootstrap.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-cat.sh.err b/go/reg-test/expected/case-verb-cat.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-cat.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-count-distinct.sh.err b/go/reg-test/expected/case-verb-count-distinct.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-count-distinct.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-count-similar.sh.err b/go/reg-test/expected/case-verb-count-similar.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-count-similar.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-count.sh.err b/go/reg-test/expected/case-verb-count.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-count.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-cut-regexed.sh.err b/go/reg-test/expected/case-verb-cut-regexed.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-cut-regexed.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-cut.sh.err b/go/reg-test/expected/case-verb-cut.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-cut.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-decimate.sh.err b/go/reg-test/expected/case-verb-decimate.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-decimate.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-fill-down.sh.err b/go/reg-test/expected/case-verb-fill-down.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-fill-down.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-flatten-unflatten.sh.err b/go/reg-test/expected/case-verb-flatten-unflatten.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-flatten-unflatten.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-flatten-unflatten.sh.out b/go/reg-test/expected/case-verb-flatten-unflatten.sh.out
index 7a4d5312f..9da474a7b 100644
--- a/go/reg-test/expected/case-verb-flatten-unflatten.sh.out
+++ b/go/reg-test/expected/case-verb-flatten-unflatten.sh.out
@@ -221,7 +221,7 @@ mlr --ixtab --ojson unflatten -s . ./reg-test/input/unflatten-input.xtab
   }
 }
 
-mlr --ixtab --ojson --iflatsep @ unflatten ./reg-test/input/unflatten-input-2.xtab
+mlr --ixtab --ojson --oflatsep @ unflatten ./reg-test/input/unflatten-input-2.xtab
 {
   "hostname": "localhost",
   "pid": 12345,
@@ -250,7 +250,7 @@ mlr --ixtab --ojson --iflatsep @ unflatten ./reg-test/input/unflatten-input-2.xt
   }
 }
 
-mlr --xtab --iflatsep . --oflatsep @ unflatten then flatten ./reg-test/input/unflatten-input.xtab
+mlr --xtab unflatten -s . then flatten -s @ ./reg-test/input/unflatten-input.xtab
 hostname                    localhost
 pid                         12345
 req@id                      6789
diff --git a/go/reg-test/expected/case-verb-fraction.sh.err b/go/reg-test/expected/case-verb-fraction.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-fraction.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-gap.sh.err b/go/reg-test/expected/case-verb-gap.sh.err
index e69de29bb..0477be76d 100644
--- a/go/reg-test/expected/case-verb-gap.sh.err
+++ b/go/reg-test/expected/case-verb-gap.sh.err
@@ -0,0 +1,10 @@
+
+Usage: mlr gap [options]
+Emits an empty record every n records, or when certain values change.
+Options:
+Emits an empty record every n records, or when certain values change.
+-g {a,b,c} Print a gap whenever values of these fields (e.g. a,b,c) changes.
+-n {n} Print a gap every n records.
+One of -f or -g is required.
+-n is ignored if -g is present.
+-h|--help Show this message.
diff --git a/go/reg-test/expected/case-verb-grep.sh.err b/go/reg-test/expected/case-verb-grep.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-grep.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-group-by.sh.err b/go/reg-test/expected/case-verb-group-by.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-group-by.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-group-like.sh.err b/go/reg-test/expected/case-verb-group-like.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-group-like.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-having-fields.sh.err b/go/reg-test/expected/case-verb-having-fields.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-having-fields.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-head.sh.err b/go/reg-test/expected/case-verb-head.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-head.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-histogram.sh.err b/go/reg-test/expected/case-verb-histogram.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-histogram.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-int-float-stats1-step1.sh.err b/go/reg-test/expected/case-verb-int-float-stats1-step1.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-int-float-stats1-step1.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-join-mixed-format.sh.err b/go/reg-test/expected/case-verb-join-mixed-format.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-join-mixed-format.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-join.sh.err b/go/reg-test/expected/case-verb-join.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-join.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-json-parse-json-stringify.sh.err b/go/reg-test/expected/case-verb-json-parse-json-stringify.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-json-parse-json-stringify.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-label.sh.err b/go/reg-test/expected/case-verb-label.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-verb-label.sh.err
+++ b/go/reg-test/expected/case-verb-label.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-nothing.sh.err b/go/reg-test/expected/case-verb-nothing.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-nothing.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-regularize.sh.err b/go/reg-test/expected/case-verb-regularize.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-regularize.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-remove-empty-columns.sh.err b/go/reg-test/expected/case-verb-remove-empty-columns.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-remove-empty-columns.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-rename-no-regex.sh.err b/go/reg-test/expected/case-verb-rename-no-regex.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-rename-no-regex.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-rename.sh.err b/go/reg-test/expected/case-verb-rename.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-verb-rename.sh.err
+++ b/go/reg-test/expected/case-verb-rename.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-reorder.sh.err b/go/reg-test/expected/case-verb-reorder.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-verb-reorder.sh.err
+++ b/go/reg-test/expected/case-verb-reorder.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-repeat.sh.err b/go/reg-test/expected/case-verb-repeat.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-repeat.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-sample.sh.err b/go/reg-test/expected/case-verb-sample.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-sample.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-sec2gmt.sh.err b/go/reg-test/expected/case-verb-sec2gmt.sh.err
index e69de29bb..8b1378917 100644
--- a/go/reg-test/expected/case-verb-sec2gmt.sh.err
+++ b/go/reg-test/expected/case-verb-sec2gmt.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-seqgen.sh.err b/go/reg-test/expected/case-verb-seqgen.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-seqgen.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-shuffle.sh.err b/go/reg-test/expected/case-verb-shuffle.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-shuffle.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-skip-trivial-records.sh.err b/go/reg-test/expected/case-verb-skip-trivial-records.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-skip-trivial-records.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-sort-within-records.sh.err b/go/reg-test/expected/case-verb-sort-within-records.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-sort-within-records.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-sort.sh.err b/go/reg-test/expected/case-verb-sort.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-sort.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-stats1-percentile-interpolation.sh.err b/go/reg-test/expected/case-verb-stats1-percentile-interpolation.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-stats1-percentile-interpolation.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-stats1.sh.err b/go/reg-test/expected/case-verb-stats1.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-stats1.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-step.sh.err b/go/reg-test/expected/case-verb-step.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-step.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-tac.sh.err b/go/reg-test/expected/case-verb-tac.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-tac.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-tail.sh.err b/go/reg-test/expected/case-verb-tail.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-tail.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-truncate.sh.err b/go/reg-test/expected/case-verb-truncate.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-truncate.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-uniq.sh.err b/go/reg-test/expected/case-verb-uniq.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-uniq.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/expected/case-verb-unsparsify.sh.err b/go/reg-test/expected/case-verb-unsparsify.sh.err
new file mode 100644
index 000000000..8b1378917
--- /dev/null
+++ b/go/reg-test/expected/case-verb-unsparsify.sh.err
@@ -0,0 +1 @@
+
diff --git a/go/reg-test/run b/go/reg-test/run
index 7f4b2d922..c0c5c0988 100755
--- a/go/reg-test/run
+++ b/go/reg-test/run
@@ -35,8 +35,8 @@ set -uo pipefail
 #
 # * Each has lines of the form 'run_mlr ...' or 'mlr_expect_fail ...'.
 #   Those functions are defined here in this file. They take mlr command-lines
-#   as arguments.  They also take global variables $verbose, $outfile, and
-#   $errfile as side-inputs, and write global variables like
+#   as arguments.  They also take global variables $verbose, $actual_stdout_file, and
+#   $actual_stderr_file as side-inputs, and write global variables like
 #   $num_invocations_passed as side-outputs.
 #
 # * Each case can fail in the following ways:
@@ -75,11 +75,11 @@ run_mlr() {
     if [ "$verbose" = "true" ]; then
       echo mlr "$@"
     fi
-    echo mlr "$@" >> $outfile
+    echo mlr "$@" >> $actual_stdout_file
     num_invocations_attempted=`expr $num_invocations_attempted + 1`
 
-    # There's no '1>> $outfile 2>> $errfile' but I'd use it if there were.
-    # Instead we use this '$errfile.$$' trick.
+    # There's no '1>> $actual_stdout_file 2>> $actual_stderr_file' but I'd use it if there were.
+    # Instead we use this '$actual_stderr_file.$$' trick.
     #
     # Also note that we could 2>&1 and have a single combined stdout-and-stderr
     # file. However, experience has shown that the line-ordering isn't
@@ -87,10 +87,10 @@ run_mlr() {
     # (and passing) on one platform to fail on another. See in particular
     # https://github.com/johnkerl/miller/issues/293
 
-    $path_to_mlr "$@" >> $outfile 2> $errfile.$$
+    $path_to_mlr "$@" >> $actual_stdout_file 2> $actual_stderr_file.$$
     status=$?
-    cat $errfile.$$ >> $errfile
-    rm $errfile.$$
+    cat $actual_stderr_file.$$ >> $actual_stderr_file
+    rm $actual_stderr_file.$$
 
     if [ $status -eq 0 ]; then
       num_invocations_passed=`expr $num_invocations_passed + 1`
@@ -98,10 +98,10 @@ run_mlr() {
       if [ "$verbose" = "true" ]; then
         echo "Exit status was $status; expected 0."
       fi
-      echo "Exit status was $status; expected 0." >> $outfile
+      echo "Exit status was $status; expected 0." >> $actual_stdout_file
       num_invocations_failed=`expr $num_invocations_failed + 1`
     fi
-    echo >> $outfile
+    echo >> $actual_stdout_file
   fi
 }
 
@@ -119,17 +119,17 @@ mlr_expect_fail() {
     if [ "$verbose" = "true" ]; then
       echo mlr "$@"
     fi
-    echo mlr "$@" >> $outfile 2> $errfile.$$
-    cat $errfile.$$ >> $errfile
-    rm $errfile.$$
+    echo mlr "$@" >> $actual_stdout_file 2> $actual_stderr_file.$$
+    cat $actual_stderr_file.$$ >> $actual_stderr_file
+    rm $actual_stderr_file.$$
     num_invocations_attempted=`expr $num_invocations_attempted + 1`
 
-    # There's no '1>> $outfile 2>> $errfile' but I'd use it if there were.
-    # Instead we use this '$errfile.$$' trick.
-    $path_to_mlr "$@" >> $outfile 2> $errfile.$$
+    # There's no '1>> $actual_stdout_file 2>> $actual_stderr_file' but I'd use it if there were.
+    # Instead we use this '$actual_stderr_file.$$' trick.
+    $path_to_mlr "$@" >> $actual_stdout_file 2> $actual_stderr_file.$$
     status=$?
-    cat $errfile.$$ >> $errfile
-    rm $errfile.$$
+    cat $actual_stderr_file.$$ >> $actual_stderr_file
+    rm $actual_stderr_file.$$
 
     if [ $status -eq 1 ]; then
       num_invocations_passed=`expr $num_invocations_passed + 1`
@@ -138,9 +138,9 @@ mlr_expect_fail() {
       if [ "$verbose" = "true" ]; then
         echo "Exit status was $status; expected 1."
       fi
-      echo "Exit status was $status; expected 1." >> $outfile
+      echo "Exit status was $status; expected 1." >> $actual_stdout_file
     fi
-    echo >> $outfile
+    echo >> $actual_stdout_file
   fi
 }
 
@@ -161,7 +161,7 @@ run_mlr_externally_redirected() {
     if [ "$verbose" = "true" ]; then
       echo mlr "$@"
     fi
-    echo mlr "$@" >> $outfile
+    echo mlr "$@" >> $actual_stdout_file
     num_invocations_attempted=`expr $num_invocations_attempted + 1`
 
     $path_to_mlr "$@" # callsite is expected to redirect stdout and stderr
@@ -173,10 +173,10 @@ run_mlr_externally_redirected() {
       if [ "$verbose" = "true" ]; then
         echo "Exit status was $status; expected 0."
       fi
-      echo "Exit status was $status; expected 0." >> $outfile
+      echo "Exit status was $status; expected 0." >> $actual_stdout_file
       num_invocations_failed=`expr $num_invocations_failed + 1`
     fi
-    echo >> $outfile
+    echo >> $actual_stdout_file
   fi
 }
 
@@ -196,12 +196,12 @@ run_mlr_no_output() {
     fi
     num_invocations_attempted=`expr $num_invocations_attempted + 1`
 
-    # There's no '1>> $outfile 2>> $errfile' but I'd use it if there were.
-    # Instead we use this '$errfile.$$' trick.
-    $path_to_mlr "$@" 2> $errfile.$$
+    # There's no '1>> $actual_stdout_file 2>> $actual_stderr_file' but I'd use it if there were.
+    # Instead we use this '$actual_stderr_file.$$' trick.
+    $path_to_mlr "$@" 2> $actual_stderr_file.$$
     status=$?
-    cat $errfile.$$ >> $errfile
-    rm $errfile.$$
+    cat $actual_stderr_file.$$ >> $actual_stderr_file
+    rm $actual_stderr_file.$$
 
     if [ $status -eq 0 ]; then
       num_invocations_passed=`expr $num_invocations_passed + 1`
@@ -209,10 +209,10 @@ run_mlr_no_output() {
       if [ "$verbose" = "true" ]; then
         echo "Exit status was $status; expected 0."
       fi
-      echo "Exit status was $status; expected 0." >> $outfile
+      echo "Exit status was $status; expected 0." >> $actual_stdout_file
       num_invocations_failed=`expr $num_invocations_failed + 1`
     fi
-    echo >> $outfile
+    echo >> $actual_stdout_file
   fi
 }
 
@@ -229,9 +229,9 @@ run_cat() {
     if [ "$verbose" = "true" ]; then
       echo cat "$@"
     fi
-    echo cat "$@" >> $outfile # for diff at end
-    cat "$@" >> $outfile      # for diff at end
-    echo >> $outfile
+    echo cat "$@" >> $actual_stdout_file # for diff at end
+    cat "$@" >> $actual_stdout_file      # for diff at end
+    echo >> $actual_stdout_file
   fi
 }
 
@@ -244,10 +244,10 @@ announce() {
     echo "$@"
   else
 
-    echo >> $outfile
-    echo "================================================================" >> $outfile
-    echo "$@" >> $outfile
-    echo >> $outfile
+    echo >> $actual_stdout_file
+    echo "================================================================" >> $actual_stdout_file
+    echo "$@" >> $actual_stdout_file
+    echo >> $actual_stdout_file
   fi
 }
 
@@ -257,8 +257,8 @@ mention() {
     echo
     echo ---------------------------------------------------------------- "$@"
   else
-    echo >> $outfile
-    echo ---------------------------------------------------------------- "$@" >> $outfile
+    echo >> $actual_stdout_file
+    echo ---------------------------------------------------------------- "$@" >> $actual_stdout_file
   fi
 }
 
@@ -404,14 +404,16 @@ for case_file in $case_file_names; do
   num_invocations_failed=0
 
   case_name=$(basename $case_file)
-  outfile=$outdir/$case_name.out
-  errfile=$outdir/$case_name.err
-  expfile=$expdir/$case_name.out
+  actual_stdout_file=$outdir/$case_name.out
+  actual_stderr_file=$outdir/$case_name.err
+  expected_stdout_file=$expdir/$case_name.out
+  expected_stderr_file=$expdir/$case_name.err
 
   case_passed=true
 
   if [ "$only_show" = "false" ]; then
-    echo > $outfile
+    echo > $actual_stdout_file
+    echo > $actual_stderr_file
   fi
   num_cases_attempted=`expr $num_cases_attempted + 1`
 
@@ -471,21 +473,28 @@ for case_file in $case_file_names; do
     if [ "$sdiff" = "true" ]; then
       # Assuming we're run interactively
       width=$(stty size | awk '{print $2}')
-      echo sdiff -w $width $diff_context_flag $expfile $outfile
-      sdiff -w $width $diff_context_flag $expfile $outfile
+      echo sdiff -w $width $diff_context_flag $expected_stdout_file $actual_stdout_file
+      sdiff -w $width $diff_context_flag $expected_stdout_file $actual_stdout_file
+      echo sdiff -w $width $diff_context_flag $expected_stderr_file $actual_stderr_file
+      sdiff -w $width $diff_context_flag $expected_stderr_file $actual_stderr_file
     else
-      echo diff -a -I '^mlr' -I '^Miller:' -I '^cat' $diff_context_flag $expfile $outfile
-      diff -a -I '^mlr' -I '^Miller:' -I '^cat' $diff_context_flag $expfile $outfile
+      echo diff -a -I '^mlr' -I '^Miller:' -I '^cat' $diff_context_flag $expected_stdout_file $actual_stdout_file
+      diff -a -I '^mlr' -I '^Miller:' -I '^cat' $diff_context_flag $expected_stdout_file $actual_stdout_file
+      echo diff -a -I '^mlr' -I '^Miller:' -I '^cat' $diff_context_flag $expected_stderr_file $actual_stderr_file
+      diff -a -I '^mlr' -I '^Miller:' -I '^cat' $diff_context_flag $expected_stderr_file $actual_stderr_file
     fi
   else
-    diff -q -a -I '^mlr' -I '^Miller:' -I '^cat' $diff_context_flag $expfile $outfile > /dev/null
+    diff -q -a -I '^mlr' -I '^Miller:' -I '^cat' $diff_context_flag $expected_stdout_file $actual_stdout_file > /dev/null
+    diff -q -a -I '^mlr' -I '^Miller:' -I '^cat' $diff_context_flag $expected_stderr_file $actual_stderr_file > /dev/null
   fi
   status=$?
   if [ $status -ne 0 ]; then
     if [ "$verbose" = "true" ]; then
       echo "Case failed due to expected output != actual output:"
-      echo "$expfile"
-      echo "$outfile"
+      echo "$expected_stdout_file"
+      echo "$actual_stdout_file"
+      echo "$expected_stderr_file"
+      echo "$actual_stderr_file"
     fi
     case_passed=false
   fi
diff --git a/go/src/dsl/cst/warn.go b/go/src/dsl/cst/warn.go
index b1da30f4a..3a8655e29 100644
--- a/go/src/dsl/cst/warn.go
+++ b/go/src/dsl/cst/warn.go
@@ -9,6 +9,7 @@ package cst
 
 import (
 	"fmt"
+	"os"
 
 	"miller/src/dsl"
 	"miller/src/lib"
@@ -106,7 +107,8 @@ func warnOnASTAux(
 				// -- not thousands of lines of Miller-DSL source code -- so
 				// people can look at their few lines of Miller-DSL code and
 				// spot their error.
-				fmt.Printf(
+				fmt.Fprintf(
+					os.Stderr,
 					"Variable name %s might not have been assigned yet.\n",
 					variableName,
 				)
diff --git a/go/todo.txt b/go/todo.txt
index 4ca395988..88044fd8b 100644
--- a/go/todo.txt
+++ b/go/todo.txt
@@ -3,7 +3,6 @@ TOP OF LIST:
 
 ! ut:
   o triple-for multi-middle case
-  o substr/error cases C <-> Go
 
 * -w's to stderr & trapping stderr in reg-test/run
 
diff --git a/go/u/accept-case b/go/u/accept-case
index d09d89413..8d73edaf4 100755
--- a/go/u/accept-case
+++ b/go/u/accept-case
@@ -3,14 +3,16 @@
 # See ./reg-test/run and ./reg-test/README.md for background on this
 # keystroke-saver.
 for arg; do
-  src=output-reg-test/$arg.out
-  if [ -f $src ]; then
-    cp $src reg-test/expected
-  elif [ -f $arg ]; then
-    src=output-reg-test/$(basename $arg).out
-    cp $src reg-test/expected
-  else
-    echo "Cannot find source $arg" 1>&2
-    exit 1
-  fi
+  for suffix in out err; do
+    src=output-reg-test/$arg.$suffix
+    if [ -f $src ]; then
+      cp $src reg-test/expected
+    elif [ -f $arg ]; then
+      src=output-reg-test/$(basename $arg).$suffix
+      cp $src reg-test/expected
+    else
+      echo "Cannot find source $arg" 1>&2
+      exit 1
+    fi
+  done
 done
diff --git a/go/u/case-diff b/go/u/case-diff
index cdde915a9..577293920 100755
--- a/go/u/case-diff
+++ b/go/u/case-diff
@@ -6,8 +6,10 @@ for arg; do
   if [ "$arg" = "-C5" ]; then
     diff_context_flag="$arg"
   else
-    expfile=./reg-test/expected/$arg.out
-    outfile=./output-reg-test/$arg.out
-    diff -a -I '^mlr' -I '^Miller:' -I '^cat' $expfile $outfile
+    for suffix in out err; do
+      expfile=./reg-test/expected/$arg.$suffix
+      outfile=./output-reg-test/$arg.$suffix
+      diff -a -I '^mlr' -I '^Miller:' -I '^cat' $expfile $outfile
+    done
   fi
 done