diff --git a/go/reg-test/expected/case-c-dsl-mapsum-mapdiff-mapexcept.sh.out b/go/reg-test/expected/case-c-dsl-mapsum-mapdiff-mapexcept.sh.out
index bccfbea82..5ed1867d1 100644
--- a/go/reg-test/expected/case-c-dsl-mapsum-mapdiff-mapexcept.sh.out
+++ b/go/reg-test/expected/case-c-dsl-mapsum-mapdiff-mapexcept.sh.out
@@ -1,55 +1,35 @@
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapsum(); dump o
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
+mlr --from ./reg-test/input/abixy-het put -q o = mapsum(); dump o
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapdiff(); dump o
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
+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
-mlr: Function named "mapexcept" takes at least 1 argument; got 0.
+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
-mlr: Function named "mapselect" takes at least 1 argument; got 0.
+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($*); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapsum($*); dump o
 {
   "a": "pan",
   "b": "pan",
@@ -121,7 +101,7 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapsum($*); dump o
   "y": 0.9526183602969864
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapsum({"a":999}); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapsum({"a":999}); dump o
 {
   "a": 999
 }
@@ -153,7 +133,7 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapsum({"a":999}); dump o
   "a": 999
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapdiff($*); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapdiff($*); dump o
 {
   "a": "pan",
   "b": "pan",
@@ -225,7 +205,7 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapdiff($*); dump o
   "y": 0.9526183602969864
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapdiff({"a":999}); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapdiff({"a":999}); dump o
 {
   "a": 999
 }
@@ -257,7 +237,7 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapdiff({"a":999}); dump o
   "a": 999
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapexcept($*); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapexcept($*); dump o
 {
   "a": "pan",
   "b": "pan",
@@ -329,7 +309,7 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapexcept($*); dump o
   "y": 0.9526183602969864
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapexcept({"a":999}); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapexcept({"a":999}); dump o
 {
   "a": 999
 }
@@ -361,51 +341,31 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapexcept({"a":999}); dump o
   "a": 999
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapselect($*); dump o
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
+mlr --from ./reg-test/input/abixy-het put -q o = mapselect($*); dump o
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapselect({"a":999}); dump o
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
+mlr --from ./reg-test/input/abixy-het put -q o = mapselect({"a":999}); dump o
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapsum($*, {"a":999}); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapsum($*, {"a":999}); dump o
 {
   "a": 999,
   "b": "pan",
@@ -479,7 +439,7 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapsum($*, {"a":999}); dump o
   "y": 0.9526183602969864
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapsum({"a":999}, $*); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapsum({"a":999}, $*); dump o
 {
   "a": "pan",
   "b": "pan",
@@ -553,7 +513,7 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapsum({"a":999}, $*); dump o
   "y": 0.9526183602969864
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapdiff($*, {"a":999}); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapdiff($*, {"a":999}); dump o
 {
   "b": "pan",
   "i": 1,
@@ -617,31 +577,23 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapdiff($*, {"a":999}); dump
   "y": 0.9526183602969864
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapdiff({"a":999}, $*); dump o
-{
-}
-{
-}
+mlr --from ./reg-test/input/abixy-het put -q o = mapdiff({"a":999}, $*); dump o
+{}
+{}
 {
   "a": 999
 }
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
+{}
+{}
+{}
+{}
+{}
 {
   "a": 999
 }
-{
-}
+{}
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapexcept($*, "a"); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapexcept($*, "a"); dump o
 {
   "b": "pan",
   "i": 1,
@@ -705,29 +657,19 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapexcept($*, "a"); dump o
   "y": 0.9526183602969864
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapexcept({"a":999}, "a"); dump o
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
+mlr --from ./reg-test/input/abixy-het put -q o = mapexcept({"a":999}, "a"); dump o
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapexcept({"a":999}, "nonesuch"); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapexcept({"a":999}, "nonesuch"); dump o
 {
   "a": 999
 }
@@ -759,15 +701,14 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapexcept({"a":999}, "nonesuc
   "a": 999
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapselect($*, "a"); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapselect($*, "a"); dump o
 {
   "a": "pan"
 }
 {
   "a": "eks"
 }
-{
-}
+{}
 {
   "a": "eks"
 }
@@ -783,13 +724,12 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapselect($*, "a"); dump o
 {
   "a": "zee"
 }
-{
-}
+{}
 {
   "a": "pan"
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapselect({"a":999}, "a"); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapselect({"a":999}, "a"); dump o
 {
   "a": 999
 }
@@ -821,29 +761,19 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapselect({"a":999}, "a"); du
   "a": 999
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapselect({"a":999}, "nonesuch"); dump o
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
+mlr --from ./reg-test/input/abixy-het put -q o = mapselect({"a":999}, "nonesuch"); dump o
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapsum($*, {"a":999}, {"b": 444}); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapsum($*, {"a":999}, {"b": 444}); dump o
 {
   "a": 999,
   "b": 444,
@@ -919,7 +849,7 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapsum($*, {"a":999}, {"b": 4
   "y": 0.9526183602969864
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapsum({"a":999}, $*, {"b": 444}); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapsum({"a":999}, $*, {"b": 444}); dump o
 {
   "a": "pan",
   "b": 444,
@@ -995,7 +925,7 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapsum({"a":999}, $*, {"b": 4
   "y": 0.9526183602969864
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapdiff($*, {"a":999}, {"b": 444}); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapdiff($*, {"a":999}, {"b": 444}); dump o
 {
   "i": 1,
   "x": 0.3467901443380824,
@@ -1051,31 +981,23 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapdiff($*, {"a":999}, {"b":
   "y": 0.9526183602969864
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapdiff({"a":999}, $*, {"b": 444}); dump o
-{
-}
-{
-}
+mlr --from ./reg-test/input/abixy-het put -q o = mapdiff({"a":999}, $*, {"b": 444}); dump o
+{}
+{}
 {
   "a": 999
 }
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
+{}
+{}
+{}
+{}
+{}
 {
   "a": 999
 }
-{
-}
+{}
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapexcept($*, "a", "b"); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapexcept($*, "a", "b"); dump o
 {
   "i": 1,
   "x": 0.3467901443380824,
@@ -1131,29 +1053,19 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapexcept($*, "a", "b"); dump
   "y": 0.9526183602969864
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapselect({"a":999}, "b", "nonesuch"); dump o
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
+mlr --from ./reg-test/input/abixy-het put -q o = mapselect({"a":999}, "b", "nonesuch"); dump o
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapselect($*, "a", "b"); dump o
+mlr --from ./reg-test/input/abixy-het put -q o = mapselect($*, "a", "b"); dump o
 {
   "a": "pan",
   "b": "pan"
@@ -1184,32 +1096,21 @@ mlr --from ././reg-test/input/abixy-het put -q o = mapselect($*, "a", "b"); dump
   "a": "zee",
   "b": "wye"
 }
-{
-}
+{}
 {
   "a": "pan",
   "b": "wye"
 }
 
-mlr --from ././reg-test/input/abixy-het put -q o = mapselect({"a":999}, "b", "nonesuch"); dump o
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
-{
-}
+mlr --from ./reg-test/input/abixy-het put -q o = mapselect({"a":999}, "b", "nonesuch"); dump o
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}
+{}