From: David Given <dg@cowlark.com>
Date: Thu, 2 Feb 2017 21:57:17 +0000 (+0100)
Subject: Tuples can be removed from a map by index.
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=708662baf7d4a65c79fbc5785f67441c6ea59ce3;p=ack.git

Tuples can be removed from a map by index.
---

diff --git a/modules/src/data/pmap.c b/modules/src/data/pmap.c
index 5eaadc2dd..bbc41e7ea 100644
--- a/modules/src/data/pmap.c
+++ b/modules/src/data/pmap.c
@@ -1,6 +1,7 @@
 #include <stdlib.h>
 #include <stdbool.h>
 #include <string.h>
+#include <assert.h>
 #include "pmap.h"
 
 static void append(void* mapp, void* left, void* right)
@@ -73,6 +74,16 @@ void pmap_add_bi(void* mapp, void* left, void* right)
     append(map, left, right);
 }
 
+void pmap_remove_index(void* mapp, int index)
+{
+    struct pmap* map = mapp;
+    struct pmap_node* node = &map->item[index];
+
+    assert((index >= 0) && (index < map->count));
+    memmove(node, node+1, sizeof(*node) * (map->count - index - 1));
+    map->count--;
+}
+
 void pmap_remove(void* mapp, void* left, void* right)
 {
     struct pmap* map = mapp;
@@ -83,8 +94,7 @@ void pmap_remove(void* mapp, void* left, void* right)
 		struct pmap_node* node = &map->item[i];
 		if ((node->left == left) && (node->right == right))
 		{
-			memmove(node, node+1, sizeof(*node) * (map->count - i - 1));
-			map->count--;
+            pmap_remove_index(map, i);
 			return;
 		}
     }
diff --git a/modules/src/data/pmap.h b/modules/src/data/pmap.h
index 9d4ec3326..3921143c0 100644
--- a/modules/src/data/pmap.h
+++ b/modules/src/data/pmap.h
@@ -26,6 +26,7 @@ struct pmap
 extern void pmap_put(void* map, void* left, void* right);
 extern void pmap_add(void* map, void* left, void* right);
 extern void pmap_add_bi(void* map, void* left, void* right);
+extern void pmap_remove_index(void* map, int index);
 extern void pmap_remove(void* map, void* left, void* right);
 extern void pmap_remove_bi(void* map, void* left, void* right);
 extern void pmap_remove_either(void* map, void* either);