new iter-iter iterator and kern.func-info module

kern/function.go

@@ -14,11 +14,6 @@ type FuncTemplate func(ctx ExprContext, name string, args map[string]any) (resul
 
 type DeepFuncTemplate func(a, b any) (eq bool, err error)
 
-func IsFunctor(v any) (ok bool) {
-	_, ok = v.(Functor)
-	return
-}
-
 // ---- Common functor definition
 type BaseFunctor struct {
 	info ExprFunc
@@ -54,17 +49,17 @@ func (functor *BaseFunctor) GetDefinitionContext() ExprContext {
 }
 
 // ---- Function Parameters
-type paramFlags uint16
+type FuncParamFlags uint16
 
 const (
-	PfDefault paramFlags = 1 << iota
+	PfDefault FuncParamFlags = 1 << iota
 	PfOptional
 	PfRepeat
 )
 
 type funcParamInfo struct {
 	name         string
-	flags        paramFlags
+	flags        FuncParamFlags
 	defaultValue any
 }
 
@@ -72,11 +67,11 @@ func NewFuncParam(name string) ExprFuncParam {
 	return &funcParamInfo{name: name}
 }
 
-func NewFuncParamFlag(name string, flags paramFlags) ExprFuncParam {
+func NewFuncParamFlag(name string, flags FuncParamFlags) ExprFuncParam {
 	return &funcParamInfo{name: name, flags: flags}
 }
 
-func NewFuncParamFlagDef(name string, flags paramFlags, defValue any) *funcParamInfo {
+func NewFuncParamFlagDef(name string, flags FuncParamFlags, defValue any) *funcParamInfo {
 	return &funcParamInfo{name: name, flags: flags, defaultValue: defValue}
 }