lang: parser: Better semantics for setting positions

lang/ast/structs.go

@@ -189,7 +189,7 @@ type TextArea struct {
 }
 
 // Locate is used by the parser to store the token positions in AST nodes
-func (a TextArea) Locate(line int, col int, endline int, endcol int) {
+func (a *TextArea) Locate(line int, col int, endline int, endcol int) {
 	a.startLine = line
 	a.startColumn = col
 	a.endLine = endline
@@ -200,6 +200,8 @@ func (a TextArea) Locate(line int, col int, endline int, endcol int) {
 // position. It is implemented by node types that embed TextArea.
 type LocalNode interface {
 	Locate(int, int, int, int)
+	GetPosition() (int, int)
+	GetEndPosition() (int, int)
 }
 
 // GetPosition returns the starting line/column of an AST node
@@ -222,7 +224,7 @@ type StmtBind struct {
 
 // String returns a short representation of this statement.
 func (obj *StmtBind) String() string {
-	return fmt.Sprintf("bind(%s)", obj.Ident)
+	return fmt.Sprintf("bind(%s) @ (%d %d)", obj.Ident, obj.startLine+1, obj.startColumn+1)
 }
 
 // Apply is a general purpose iterator method that operates on any AST node. It
@@ -255,10 +257,9 @@ func (obj *StmtBind) Interpolate() (interfaces.Stmt, error) {
 	if err != nil {
 		return nil, err
 	}
-	return &StmtBind{
-		Ident: obj.Ident,
-		Value: interpolated,
-	}, nil
+	result := *obj
+	result.Value = interpolated
+	return &result, nil
 }
 
 // Copy returns a light copy of this struct. Anything static will not be copied.
@@ -2610,6 +2611,8 @@ func (obj *StmtIf) String() string {
 		s += fmt.Sprintf(" else { %s }", obj.ElseBranch.String())
 	}
 
+	s += fmt.Sprintf(" @ (%d %d)", obj.startLine+1, obj.startColumn+1)
+
 	return s
 }
 
@@ -2676,11 +2679,11 @@ func (obj *StmtIf) Interpolate() (interfaces.Stmt, error) {
 			return nil, errwrap.Wrapf(err, "could not interpolate ElseBranch")
 		}
 	}
-	return &StmtIf{
-		Condition:  condition,
-		ThenBranch: thenBranch,
-		ElseBranch: elseBranch,
-	}, nil
+	result := *obj
+	result.Condition = condition
+	result.ThenBranch = thenBranch
+	result.ElseBranch = elseBranch
+	return &result, nil
 }
 
 // Copy returns a light copy of this struct. Anything static will not be copied.

lang/gapi/gapi.go

@@ -261,6 +261,12 @@ func (obj *GAPI) Cli(info *gapi.Info) (*gapi.Deploy, error) {
 		return nil, nil // success!
 	}
 
+	fmt.Println("The Interpolated Tree: %+v")
+	iast.Apply(func (n interfaces.Node) error {
+		fmt.Println(n)
+		return nil
+	})
+
 	if !args.SkipUnify {
 		// apply type unification
 		unificationLogf := func(format string, v ...interface{}) {