diff --git a/libftasm/ft_id.c b/libftasm/ft_id.c
index ab2bb70f..e5624755 100644
--- a/libftasm/ft_id.c
+++ b/libftasm/ft_id.c
@@ -1,6 +1,6 @@
 #include "libft.h"
 
-void	*ft_id(void *a)
+t_list	*ft_id(t_list *a)
 {
 	return (a);
 }
diff --git a/libftasm/ft_lst_cfree.c b/libftasm/ft_lst_cfree.c
new file mode 100644
index 00000000..deb40281
--- /dev/null
+++ b/libftasm/ft_lst_cfree.c
@@ -0,0 +1,8 @@
+#include "libft.h"
+
+void	ft_lst_cfree(void *ptr, size_t size)
+{
+	(void)size;
+	if (ptr)
+		free(ptr);
+}
diff --git a/libftasm/ft_lst_remove_if.c b/libftasm/ft_lst_delif.c
similarity index 53%
rename from libftasm/ft_lst_remove_if.c
rename to libftasm/ft_lst_delif.c
index 2e96a970..b2943895 100644
--- a/libftasm/ft_lst_remove_if.c
+++ b/libftasm/ft_lst_delif.c
@@ -1,29 +1,25 @@
 #include "libft.h"
 
-void	ft_lst_remove_if(
-		t_list **begin_list,
-		void *data_ref,
-		int (*cmp)())
+void	ft_lst_delif(t_list **alst, void *data_ref, int (*cmp)(), void (*del)(void *, size_t))
 {
 	t_list	*last;
 	t_list	*current;
 	t_list	*tmp;
 
 	last = NULL;
-	current = *begin_list;
+	current = *alst;
 	tmp = NULL;
-	fflush(stdout);
 	while (current)
 	{
-		if ((*cmp)(current->content, &data_ref) == 0)
+		if ((*cmp)(current->content, data_ref) == 0)
 		{
-			if (current == *begin_list)
-				*begin_list = current->next;
+			if (current == *alst)
+				*alst = current->next;
 			else
 				last->next = current->next;
 			tmp = current;
 			current = current->next;
-			free(tmp);
+			ft_lstdelone(&tmp, del);
 		}
 		else
 		{
diff --git a/libftasm/ft_lst_remove_sub.c b/libftasm/ft_lst_delsub.c
similarity index 71%
rename from libftasm/ft_lst_remove_sub.c
rename to libftasm/ft_lst_delsub.c
index e419b285..1d57c477 100644
--- a/libftasm/ft_lst_remove_sub.c
+++ b/libftasm/ft_lst_delsub.c
@@ -1,6 +1,6 @@
 #include "libft.h"
 
-void	ft_lstdelsub(t_list **alst, t_list *sub, int (*cmp)(), void (*del)(void *, size_t))
+void	ft_lst_delsub(t_list **alst, t_list *sub, int (*cmp)(), void (*del)(void *, size_t))
 {
 	t_list	*last;
 	t_list	*current;
@@ -11,6 +11,11 @@ void	ft_lstdelsub(t_list **alst, t_list *sub, int (*cmp)(), void (*del)(void *,
 	tmp = NULL;
 	while (current && sub)
 	{
+		if ((*cmp)(current->content, sub->content) > 0)
+		{
+			sub = sub->next;
+			continue ;
+		}
 		if ((*cmp)(current->content, sub->content) == 0)
 		{
 			if (current == *alst)
diff --git a/libftasm/ft_lst_filter.c b/libftasm/ft_lst_filter.c
new file mode 100644
index 00000000..537dbb47
--- /dev/null
+++ b/libftasm/ft_lst_filter.c
@@ -0,0 +1,24 @@
+#include "libft.h"
+
+t_list	*ft_lst_filter(t_list *lst, void const *data_ref, t_list *(*f)(t_list *elem, void const *))
+{
+	t_list	*out;
+	t_list	*elem;
+
+	out = NULL;
+	while (lst)
+	{
+		elem = (*f)(lst, data_ref);
+		/* printf("size=%zu\n", elem->content_size); */
+		/* printf("content=%i\n", *(int*)elem->content); */
+		/* fflush(stdout); */
+		elem = ft_lstnew(elem->content, elem->content_size);
+		/* printf("size=%zu\n", elem->content_size); */
+		/* printf("content=%i\n", *(int*)elem->content); */
+		/* fflush(stdout); */
+		ft_lsteadd(&out, elem);
+		lst = lst->next;
+	}
+	/* ft_lst_print(out, &ft_putnbr); */
+	return (out);
+}
diff --git a/libftasm/ft_lstdelone.c b/libftasm/ft_lstdelone.c
index e2de5a66..c1c26741 100644
--- a/libftasm/ft_lstdelone.c
+++ b/libftasm/ft_lstdelone.c
@@ -2,7 +2,11 @@
 
 void	ft_lstdelone(t_list **alst, void (*del)(void *, size_t))
 {
-	(*del)((*alst)->content, (*alst)->content_size);
-	free(*alst);
+	if (*alst)
+	{
+		if (del)
+			(*del)((*alst)->content, (*alst)->content_size);
+		free(*alst);
+	}
 	*alst = NULL;
 }
diff --git a/libftasm/libft.h b/libftasm/libft.h
index c03f0d44..e0efb934 100644
--- a/libftasm/libft.h
+++ b/libftasm/libft.h
@@ -89,7 +89,11 @@ t_list	*ft_lstlast(t_list *lst);
 void	ft_lst_sorted_merge(t_list **begin_list1, t_list *begin_list2, int (*cmp)());
 void	ft_lst_sorted_insert(t_list **begin_list, t_list *insert, int (*cmp)());
 t_list	*ft_lstnew_range(int a, int b);
+void	ft_lst_delif(t_list **alist, void *data_ref, int (*cmp)(), void (*del)(void *, size_t));
+void	ft_lst_delsub(t_list **alst, t_list *sub, int (*cmp)(), void (*del)(void *, size_t));
+void	ft_lst_cfree(void *ptr, size_t size);
+t_list	*ft_lst_filter(t_list *lst, void const *data_ref, t_list *(*f)(t_list *elem, void const *));
 
 int		ft_diff(void *a, void *b);
-void	*ft_id(void *a);
+t_list	*ft_id(t_list *a);
 #endif