diff --git a/includes/list.h b/includes/list.h
index dcff1f7..6d01119 100644
--- a/includes/list.h
+++ b/includes/list.h
@@ -14,8 +14,8 @@ typedef struct {
 } List;
 
 List* CreateList(void);
-int AddListItem(char *, List *);
-void PrintList(List*);
+int AddListItem(const char *, List *);
+void PrintList(const List*);
 void DestroyList(List*);
 
 #endif
\ No newline at end of file
diff --git a/src/list.c b/src/list.c
index fa5fbbf..1fb806b 100644
--- a/src/list.c
+++ b/src/list.c
@@ -9,11 +9,17 @@ List* CreateList() {
     return new;
 }
 
-int AddListItem(char *value, List* list) {
+int AddListItem(const char *value, List* list) {
     if (list == NULL) return -1;
 
     if (list->capacity < list->size + 1) {
-        list->root = realloc(list->root, sizeof(char*) * list->capacity * 2);
+        void* ptr = realloc(list->root, sizeof(char*) * list->capacity * 2);
+        //Note: realloc will free list->root if it succeeds.
+        if (!ptr) {
+            return -1;
+        }
+
+        list->root = ptr;
         list->capacity = list->capacity * 2;
     }
 
@@ -28,10 +34,10 @@ int AddListItem(char *value, List* list) {
     return 0;
 }
 
-void PrintList(List* list) {
+void PrintList(const List* list) {
     if (list == NULL) return;
 
-    List *current = list;
+    const List *current = list;
 
     printf("Size: %d; Capacity: %d\n", list->size, list->capacity);