include_once support for javascript

The include syntax was changed and enhanced by a include_once statement.

Syntax:

/* DOKUWIKI:include somefile.js */
/* DOKUWIKI:include_once someotherfile.js */

Note: include_once uses the basename of the inlcuded file to determine if
      it was previously loaded. You need to use something unique for it to
      make sure it is correctly loaded.

Note: included files are not checked for updates by the cache logic. You
      need to touch the master file for updating the cache

Note: includes are *not* supported inside included files to avoid any
      circular references

darcs-hash:20070513222421-7ad00-d99d717ba8a428d0af2b3f7d593897e0467cb9c9.gz

lib/exe/js.php

@@ -165,13 +165,24 @@ function js_out(){
 
 /**
  * Load the given file, handle include calls and print it
+ *
+ * @author Andreas Gohr <andi@splitbrain.org>
  */
 function js_load($file){
     if(!@file_exists($file)) return;
+    static $loaded = array();
 
     $data = io_readFile($file);
-    while(preg_match('#/\*\s*!!include\s+([\w\./]+)\s*\*/#',$data,$match)){
-        $ifile = $match[1];
+    while(preg_match('#/\*\s*DOKUWIKI:include(_once)\s+([\w\./]+)\s*\*/#',$data,$match)){
+        $ifile = $match[2];
+
+        // is it a include_once?
+        if($match[1]){
+            $base = basename($ifile);
+            if($loaded[$base]) continue;
+            $loaded[$base] = true;
+        }
+
         if($ifile{0} != '/') $ifile = dirname($file).'/'.$ifile;
 
         if(@file_exists($ifile)){