c/reg_test/run reorg

go/README.md

@@ -124,7 +124,8 @@ nil through the reader/mapper/writer sequence.
   * If a mapper drops a record (`mlr filter` in false cases, for example, or `mlr nothing`) it will be GCed.
   * One caveat is any mapper which produces multiples, e.g. `mlr repeat` -- this needs to explicitly copy records instead of producing multiple pointers to the same record.
 * Right-hand-sides of DSL expressions all pass around pointers to records and Mlrvals.
-* Copy-on-write is done on map/array put -- for example, in the assignment phase of a DSL statement.
+  * Lvalue expressions return pointed `*lib.Mlrmap` so they can be assigned to; rvalue expressions return non-pointed `lib.Mlrval` but these are very shallow copies -- the int/string/etc types are copied but maps/arrays are passed by reference in the rvalue expression-evaluators.
+* Copy-on-write is done on map/array put -- for example, in the assignment phase of a DSL statement, where an rvalue is assigned to an lvalue.
 
 # More about mlrvals
 

go/src/miller/dsl/cst/lvalues.go

@@ -96,7 +96,6 @@ func BuildIndirectFieldValueLvalueNode(astNode *dsl.ASTNode) (IAssignable, error
 	lib.InternalCodingErrorIf(astNode.Type != dsl.NodeTypeIndirectFieldValue)
 	lib.InternalCodingErrorIf(astNode == nil)
 	lib.InternalCodingErrorIf(len(astNode.Children) != 1)
-
 	lhsFieldNameExpression, err := BuildEvaluableNode(astNode.Children[0])
 	if err != nil {
 		return nil, err
@@ -385,7 +384,6 @@ func BuildIndexedLvalueNode(astNode *dsl.ASTNode) (IAssignable, error) {
 			break
 		}
 	}
-
 	return NewIndexedLvalueNode(baseLvalue, indexEvaluables), nil
 }
 

go/src/miller/dsl/cst/root.go

@@ -101,7 +101,7 @@ func (this *RootNode) ExecuteBeginBlocks(state *State) error {
 func (this *RootNode) ExecuteMainBlock(state *State) (outrec *lib.Mlrmap, err error) {
 	err = this.mainBlock.Execute(state)
 
-	return state.Inrec, nil
+	return state.Inrec, err
 }
 
 // ----------------------------------------------------------------

go/src/miller/lib/mlrmap_accessors.go

@@ -110,6 +110,7 @@ func (this *Mlrmap) PutIndexedKeyless(indices []*Mlrval, rvalue *Mlrval) error {
 	}
 
 	baseIndex := indices[0]
+	// yyy string/positional-int
 	if !baseIndex.IsString() {
 		skey := baseIndex.String()
 		return errors.New("Non-string key " + skey) // xxx needs better wording
@@ -117,10 +118,13 @@ func (this *Mlrmap) PutIndexedKeyless(indices []*Mlrval, rvalue *Mlrval) error {
 	baseKey := baseIndex.printrep
 
 	if n == 1 {
+		// yyy PutCopy w/ Mlrval flavor
+		// yyy sigh ... doc that positional indices on maps don't auto-extend.
 		this.PutCopy(&baseKey, rvalue) // E.g. mlr put '$*["a"] = 3'
 		return nil
 	}
 
+	// yyy Get w/ Mlrval flavor
 	baseValue := this.Get(&baseKey)
 	if baseValue == nil {
 		baseValue := MlrvalEmptyMap()

go/todo.txt

@@ -1,7 +1,7 @@
 ----------------------------------------------------------------
 TOP OF LIST:
 
-* wednesday:
+* thursday:
   ! array-assigns with auto-extend
     k API:
       k mlrmap.GetWithPositionalIndex
@@ -10,7 +10,8 @@ TOP OF LIST:
     k code/test '$new = $*[1]'
     o code/test '$[1] = "new"'
     o code/test '$*[1] = "new"'
-    o this needs to work: '@records[FILENAME][NR]=$*'
+    o this auto-extend needs to work: '@records[FILENAME][NR]=$*'
+  o c/reg_test/run reorgs
   ! unbork pprint writer
   o indexed-lvalue assignment ops -- need ints too
     - $[1] is easier now; needn't $[[[1]]]
@@ -108,6 +109,7 @@ PARSER/LEXER PLAN:
 NITS/NON-IMMEDIATE:
 
 * address all manner of xxx and TODO comments
+* throughout -- 'map' used too much -- 'mapping/mapper' -> 'transform' or something?
 * AST insertions: make a simple NodeFromToken & have all interface{} be *ASTNode, not *token.Token
 * mlr --help-for w/ stdout redirect for manpage -- ?
 * mlr verb -h -> stdout & exit 0
@@ -141,3 +143,8 @@ NITS/NON-IMMEDIATE:
 * support 0b0101 et al.? mlrdoc if so
 ? dsl/ast.go -> parsing/ast.go? then, put new-ast ctor -> parsing package
   o if so, update r.mds
+* mlrdoc the confusing fact that arrays are 0-up but positionals are 1-up (b/c unix toolkit)
+  o -n..-1 aliased to 0..n-1 vs -n..-1 aliased to 1..n
+  o also $1 vs $[1] -- the former 'sticks' with input-data ordering
+  o moral: miller is a name-indexed tool as its primary purpose. positional
+    indexing is supported but it can be confusing.

go/tools/mcountlines

@@ -4,3 +4,11 @@ wc -l \
   $(find src/miller -name \*.go | grep -v src/miller/parsing) \
   src/miller/parsing/mlr.bnf \
 | sort -n
+
+echo
+wc -c \
+  $(find src/miller -name \*.go | grep -v src/miller/parsing) \
+  src/miller/parsing/mlr.bnf \
+| sort -n \
+| tail -n 5
+