Variable references belonging to the parent scope added ('@')

operand-func.go

@@ -6,7 +6,6 @@ package expr
 
 import (
 	"errors"
-	"fmt"
 )
 
 // -------- function call term
@@ -24,7 +23,8 @@ func newFuncCallTerm(tk *Token, args []*term) *term {
 }
 
 // -------- eval func call
-func evalFuncCall(ctx exprContext, self *term) (v any, err error) {
+func evalFuncCall(parentCtx exprContext, self *term) (v any, err error) {
+	ctx := parentCtx.Clone()
 	name, _ := self.tk.Value.(string)
 	params := make([]any, len(self.children))
 	for i, tree := range self.children {
@@ -35,7 +35,12 @@ func evalFuncCall(ctx exprContext, self *term) (v any, err error) {
 		params[i] = param
 	}
 	if err == nil {
-		v, err = ctx.Call(name, params)
+		if v, err = ctx.Call(name, params); err == nil {
+			for _, refName := range ctx.EnumVars(func(name string) bool { return name[0] == '@' }) {
+				refValue, _ := ctx.GetVar(refName)
+				parentCtx.SetVar(refName[1:], refValue)
+			}
+		}
 	}
 	return
 }
@@ -61,8 +66,7 @@ type funcDefFunctor struct {
 	expr   Expr
 }
 
-func (functor *funcDefFunctor) Invoke(parentCtx exprContext, name string, args []any) (result any, err error) {
-	ctx := parentCtx.Clone()
+func (functor *funcDefFunctor) Invoke(ctx exprContext, name string, args []any) (result any, err error) {
 	for i, p := range functor.params {
 		if i < len(args) {
 			ctx.SetVar(p, args[i])
@@ -78,13 +82,14 @@ func evalFuncDef(ctx exprContext, self *term) (v any, err error) {
 	bodySpec := self.value()
 	if expr, ok := bodySpec.(*ast); ok {
 		paramList := make([]string, 0, len(self.children))
-		for i, param := range self.children {
-			if paramName, ok := param.value().(string); ok {
-				paramList = append(paramList, paramName)
-			} else {
-				err = fmt.Errorf("invalid function definition: formal param nr %d must be an identifiers", i+1)
-				break
-			}
+		for _, param := range self.children {
+			paramList = append(paramList, param.source())
+			// if paramName, ok := param.value().(string); ok {
+			// 	paramList = append(paramList, paramName)
+			// } else {
+			// 	err = fmt.Errorf("invalid function definition: formal param nr %d must be an identifier", i+1)
+			// 	break
+			// }
 		}
 		v = &funcDefFunctor{
 			params: paramList,