new type LinkedList, preliminary implementation

builtin-base.go

@@ -275,6 +275,16 @@ func charFunc(ctx kern.ExprContext, name string, args map[string]any) (result an
 	return
 }
 
+func seqFunc(ctx kern.ExprContext, name string, args map[string]any) (result any, err error) {
+	list := kern.NewLinkedList()
+	items := args[kern.ParamValue].([]any)
+	for _, arg := range items {
+		list.PushBack(arg)
+	}
+	result = list
+	return
+}
+
 //// import
 
 func ImportBuiltinsFuncs(ctx kern.ExprContext) {
@@ -318,6 +328,10 @@ func ImportBuiltinsFuncs(ctx kern.ExprContext) {
 	ctx.RegisterFunc("char", kern.NewGolangFunctor(charFunc), kern.TypeString, []kern.ExprFuncParam{
 		kern.NewFuncParam(kern.ParamValue),
 	})
+
+	ctx.RegisterFunc("seq", kern.NewGolangFunctor(seqFunc), kern.TypeLinkedList, []kern.ExprFuncParam{
+		kern.NewFuncParamFlag(kern.ParamValue, kern.PfRepeat),
+	})
 }
 
 func init() {