add a way to unregister snippets

demo/kitchen-sink/demo.js

@@ -450,14 +450,20 @@ require("ace/placeholder").PlaceHolder;
 var SnippetManager = require("ace/snippets").SnippetManager
 var jsSnippets = require("ace/snippets/javascript");
 window.SnippetManager = SnippetManager
+saveSnippets()
 
 function saveSnippets() {
     jsSnippets.snippets = SnippetManager.parseSnippetFile(jsSnippets.snippetText);
+    SnippetManager.snipp
     SnippetManager.register(jsSnippets.snippets, "javascript")
 }
 
 env.editSnippets = function() {
     var sp = env.split;
+    if (sp.getSplits() == 2) {
+        sp.setSplits(1);
+        return;
+    }
     sp.setSplits(1);
     sp.setSplits(2);
     sp.setOrientation(sp.BESIDE);

lib/ace/snippets.js

@@ -404,6 +404,7 @@ var SnippetManager = function() {
     this.register = function(snippets, scope) {
         var snippetMap = this.snippetMap;
         var snippetNameMap = this.snippetNameMap;
+        var self = this;
         function wrapRegexp(src) {
             if (src && !/^\^?\(.*\)\$?$|^\\b$/.test(src))
                 src = "(?:" + src + ")"
@@ -433,9 +434,15 @@ var SnippetManager = function() {
                 snippetMap[scope] = [];
                 snippetNameMap[scope] = {};
             }
+
+            var map = snippetNameMap[scope];
+            if (s.name) {
+                var old = map[s.name];
+                if (old)
+                    self.unregister(old);
+                map[s.name] = s;
+            }
             snippetMap[scope].push(s);
-            if (s.name)
-                snippetNameMap[scope][s.name] = s;
 
             if (s.tabTrigger && !s.trigger) {
                 if (!s.guard && /^\w/.test(s.tabTrigger))
@@ -455,6 +462,25 @@ var SnippetManager = function() {
         else if (Array.isArray(snippets))
             snippets.forEach(addSnippet);
     };
+    this.unregister = function(snippets, scope) {
+        var snippetMap = this.snippetMap;
+        var snippetNameMap = this.snippetNameMap;
+
+        function removeSnippet(s) {
+            var map = snippetNameMap[scope];
+            if (map && map[s.name]) {
+                delete map[s.name];
+                map = snippetMap[scope];
+                var i = map && map.indexOf(s);
+                if (i >= 0)
+                    map.splice(i, 1);
+            }
+        }
+        if (snippets.content)
+            removeSnippet(snippets);
+        else if (Array.isArray(snippets))
+            snippets.forEach(removeSnippet);
+    };
     this.parseSnippetFile = function(str) {
         var list = [], snippet = {};
         var re = /^#.*|^({[\s\S]*})\s*$|^(\S+) (.*)$|^((?:\n*\t.*)+)/gm;

lib/ace/snippets/javascript.snippets

@@ -163,13 +163,13 @@ snippet for-
 	}
 # for (...) {...}
 snippet for
-	for (var ${1:i} = 0; $1 < ${2:Things}.length; $1${3:++}) {
-		${0:$2[$1]}
+	for (var ${1:i} = 0; $1 < ${2:Things}.length; $1$++) {
+		${3:$2[$1]}$0
 	}
 # for (...) {...} (Improved Native For-Loop)
 snippet forr
-	for (var ${1:i} = ${2:Things}.length - 1; $1 >= 0; $1${3:--}) {
-		${0:$2[$1]}
+	for (var ${1:i} = ${2:Things}.length - 1; $1 >= 0; $1$--) {
+		${3:$2[$1]}$0
 	}