From daca05e637ab441d133592da165507eea119c3e3 Mon Sep 17 00:00:00 2001
From: Celestino Amoroso <celestino.amoroso@gmail.com>
Date: Mon, 13 Jul 2026 14:27:18 +0200
Subject: [PATCH] linked-list: sum and in operators

---
 operator-in.go                 |  4 ++++
 operator-sum.go                |  2 +-
 t_list_test.go                 |  8 ++++++--
 types/list/linked-list-type.go | 10 ++++++++++
 types/list/linked-list.go      | 21 ++++++++++++++++++---
 5 files changed, 39 insertions(+), 6 deletions(-)

diff --git a/operator-in.go b/operator-in.go
index beb6954..0ffc5dc 100644
--- a/operator-in.go
+++ b/operator-in.go
@@ -9,6 +9,7 @@ import (
 	"git.portale-stac.it/go-pkg/expr/scan"
 	"git.portale-stac.it/go-pkg/expr/types/array"
 	"git.portale-stac.it/go-pkg/expr/types/dict"
+	"git.portale-stac.it/go-pkg/expr/types/list"
 )
 
 //-------- in term
@@ -41,6 +42,9 @@ func evalIn(ctx kern.ExprContext, opTerm *scan.Term) (v any, err error) {
 	} else if dict.IsDict(rightValue) {
 		dict, _ := rightValue.(*dict.DictType)
 		v = dict.HasKey(leftValue)
+	} else if list.IsLinkedList(rightValue) {
+		ls, _ := rightValue.(*list.LinkedList)
+		v = ls.HasValue(leftValue)
 	} else {
 		err = opTerm.ErrIncompatibleTypes(leftValue, rightValue)
 	}
diff --git a/operator-sum.go b/operator-sum.go
index 218f238..904d727 100644
--- a/operator-sum.go
+++ b/operator-sum.go
@@ -55,7 +55,7 @@ func sumValues(plusTerm *scan.Term, leftValue, rightValue any) (v any, err error
 		lsLeft := leftValue.(*list.LinkedList)
 		lsRight := rightValue.(*list.LinkedList)
 		ls := lsLeft.Clone()
-		ls.SeqPushBack(NewLinkedListIterator(lsRight, nil))
+		ls.SeqClonePushBack(NewLinkedListIterator(lsRight, nil))
 		v = ls
 	} else if (fract.IsFraction(leftValue) && types.IsNumber(rightValue)) || (fract.IsFraction(rightValue) && types.IsNumber(leftValue)) {
 		if float.IsFloat(leftValue) || float.IsFloat(rightValue) {
diff --git a/t_list_test.go b/t_list_test.go
index 3a87455..24d040a 100644
--- a/t_list_test.go
+++ b/t_list_test.go
@@ -11,8 +11,8 @@ import (
 	"git.portale-stac.it/go-pkg/expr/types/list"
 )
 
-func TestListParser(t *testing.T) {
-	section := "List"
+func TestArray(t *testing.T) {
+	section := "Array"
 
 	inputs := []inputType{
 		/*   1 */ {`[]`, array.NewArrayA(), nil},
@@ -76,6 +76,10 @@ func TestLinkedListParser(t *testing.T) {
 		/*   3 */ {`it=$([<1,2,3>]); #($$(it))`, int64(3), nil},
 		/*   4 */ {`[<1,2,3>][0]`, int64(1), nil},
 		/*   5 */ {`[<1,2,3>][0:2]`, list.NewLinkedListA(1, 2), nil},
+		/*   6 */ {`[<1>] + [<2,3>]`, list.NewLinkedListA(1, 2, 3), nil},
+		/*   7 */ {`L=[<1>] + [<2,3>]; L[0]=100; L`, list.NewLinkedListA(100, 2, 3), nil},
+		/*   8 */ {`builtin "base"; L=[<1>]; isList(L)`, true, nil},
+		/*   9 */ {`2 IN [<1,2,3>]`, true, nil},
 	}
 
 	// t.Setenv("EXPR_PATH", ".")
diff --git a/types/list/linked-list-type.go b/types/list/linked-list-type.go
index 7a8d0ec..b0ad30d 100644
--- a/types/list/linked-list-type.go
+++ b/types/list/linked-list-type.go
@@ -127,3 +127,13 @@ func (ls1 *LinkedList) Clone() (ls2 *LinkedList) {
 	}
 	return
 }
+
+func (ls *LinkedList) HasValue(value any) (found bool) {
+	for node := ls.FirstNode(); node != nil; node = node.Next() {
+		if kern.Equal(node.Data(), value) {
+			found = true
+			break
+		}
+	}
+	return
+}
diff --git a/types/list/linked-list.go b/types/list/linked-list.go
index d652187..6a93b38 100644
--- a/types/list/linked-list.go
+++ b/types/list/linked-list.go
@@ -85,7 +85,7 @@ func (ls *LinkedList) PushBack(data any) (node *ListNode) {
 func (ls *LinkedList) SeqPushBack(data any) (result *LinkedList) {
 	switch seq := data.(type) {
 	case kern.Iterator:
-		result = ls.IterPushBack(seq)
+		result = ls.IterPushBack(seq, false)
 	default:
 		ls.PushBack(data)
 		result = ls
@@ -93,9 +93,24 @@ func (ls *LinkedList) SeqPushBack(data any) (result *LinkedList) {
 	return
 }
 
-func (ls *LinkedList) IterPushBack(it kern.Iterator) *LinkedList {
+func (ls *LinkedList) SeqClonePushBack(data any) (result *LinkedList) {
+	switch seq := data.(type) {
+	case kern.Iterator:
+		result = ls.IterPushBack(seq, true)
+	default:
+		ls.PushBack(data)
+		result = ls
+	}
+	return
+}
+
+func (ls *LinkedList) IterPushBack(it kern.Iterator, clone bool) *LinkedList {
 	for item, err1 := it.Next(); err1 == nil; item, err1 = it.Next() {
-		ls.PushBack(item)
+		if clone && kern.IsCloner(item) {
+			item = item.(kern.Cloner).Clone()
+		} else {
+			ls.PushBack(item)
+		}
 	}
 	return ls
 }