Add swap_pop function for vectors

3 files changed, 44 insertions, 1 deletions

diff --git a/collections/vector/vector.adoc b/collections/vector/vector.adoc
index cc83375..ee453ff 100644
--- a/collections/vector/vector.adoc
+++ b/collections/vector/vector.adoc
@@ -1,7 +1,7 @@
 Vector
 ======
 Tucker Evans
-v0.11, 2020-07-03
+v0.12, 2020-07-03
 
 A basic vector, that hold pointers to your data structures.
 
@@ -283,6 +283,34 @@ assert(str_cmp(vec_index(vector, 0), str2) == 0);
 assert(str_cmp(vec_back(vector), str1) == 0);
 ----
 
+[[vec_swap_pop]]
++void* vec_swap_pop(vec *self, int index)+
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Swaps back element with item at +index+, and pops item now at back.
+Will return same element as +vec_remove(self, index)+.
+Does not keep order of elements, but faster that <<vec_remove,+vec_remove()+>>.
+
+Examples
+^^^^^^^^
+[source,c]
+----
+#include "vector.h"
+#include <string.h>
+
+char *str1 = "ONE";
+char *str2 = "TWO";
+char *str3 = "THREE";
+
+vec *vector = vec_new();
+vec_push(vector, str_dup(str1));
+vec_push(vector, str_dup(str2));
+vec_push(vector, str_dup(str3));
+
+assert(str_cmp(vec_swap_pop(vector, 2), str3) == 0);
+assert(str_cmp(vec_back(vector, str2) == 0);
+assert(vec_size == 2);
+----
+
 [[vec_clear]]
 +void vec_clear(vec *self)+
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/collections/vector/vector.c b/collections/vector/vector.c
index a7e0845..9ae30c7 100644
--- a/collections/vector/vector.c
+++ b/collections/vector/vector.c
@@ -190,6 +190,20 @@ int i,j;
 	return;
 }
 
+void* vec_swap_pop(root, i)
+vec *root;
+int i;
+{
+	void *tmp;
+	int j;
+
+	if (!root || i >= root->end || i < 0 || root->end <= 0)
+		return NULL;
+
+	vec_swap(root, i, root->end - 1);
+	return vec_pop(root);
+}
+
 void vec_clear(root)
 vec *root;
 {
diff --git a/collections/vector/vector.h b/collections/vector/vector.h
index 2b1e8e9..55e9481 100644
--- a/collections/vector/vector.h
+++ b/collections/vector/vector.h
@@ -22,6 +22,7 @@ void vec_set(vec*, int, void*);
 void* vec_index(vec*, int);
 
 void vec_swap(vec*, int, int);
+void* vec_swap_pop(vec*, int);
 
 
 /*memory*/