util files moved form kern to util package

helpers.go

@@ -11,6 +11,7 @@ import (
 	"strings"
 
 	"git.portale-stac.it/go-pkg/expr/kern"
+	"git.portale-stac.it/go-pkg/expr/util"
 )
 
 func EvalString(ctx kern.ExprContext, source string) (result any, err error) {
@@ -38,7 +39,7 @@ func EvalStringA(source string, args ...Arg) (result any, err error) {
 func EvalStringV(source string, args []Arg) (result any, err error) {
 	ctx := NewSimpleStoreWithoutGlobalContext()
 	for _, arg := range args {
-		if kern.IsFunc(arg.Value) {
+		if util.IsFunc(arg.Value) {
 			if f, ok := arg.Value.(kern.FuncTemplate); ok {
 				functor := kern.NewGolangFunctor(f)
 				// ctx.RegisterFunc(arg.Name, functor, 0, -1)