#4. Also... on 21 March 2008

Also from the site I just mentioned, here's a function which returns a genuine array (this could probably be combined with your function to test for preserve_keys and if not present, return a genuine array?):

function array_reverse(arr) {
  /* Simulate copy by value */
  var arr_rev = [];
  for (var i = 0; i < arr.length; i++) {
    arr_rev[i] = arr[i];
  }
  arr_rev.reverse();
  return arr_rev;
}

#3. Brett Zamir on 21 March 2008

Seems you've already done a whole lot of work, but not knowing about your site, I had started a wiki to keep this kind of information: http://javascript.wikia.com/wiki/PHP-Javascript . There are a few functions there presently, but please feel free to consider hosting this at such a wiki so it can be easily maintained by the whole community! Thanks! Email me at brettz9 & yahoo if you like.

#2. Kevin on 16 February 2008

@ Karol Kowalski: That's solid work you can take pride in Karol, thank you!

#1. Karol Kowalski on 12 February 2008

Hello, I've done some code refactoring, making the code do what it really needs to do (there's no need for the 2nd loop, it there?). I've run a test and it seems to be 38% faster. Here's the code

function array_reverse( array, preserve_keys ) {
    // http://kevin.vanzonneveld.net
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // *     example 1: array_reverse( [ 'php', '4.0', ['green', 'red'] ], true );
    // *     returns 1: { 2: ['green', 'red'], 1: 4, 0: 'php'}
 
    var i=0, f, key, keys = [], key_cnt=0, tmp_ar = {};
 
    for(key in array){
        keys[i++] = key;
    }
    keys = keys.reverse();
    key_cnt = keys.length;
    for( i=0; i < key_cnt; i++ ){
        tmp_ar[(preserve_keys ? keys[i] : i)] = array[keys[i]];
    }
 
    return tmp_ar;
}
 
function array_reverse2( array, preserve_keys ) {
    // http://kevin.vanzonneveld.net
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // *     example 1: array_reverse( [ 'php', '4.0', ['green', 'red'] ], true );
    // *     returns 1: { 2: ['green', 'red'], 1: 4, 0: 'php'}
 
  var arr_len=array.length, newkey=0, tmp_ar = {}
   
    for(var key in array){
    newkey=arr_len-key-1;
        tmp_ar[(!!preserve_keys)?newkey:key]=array[newkey]
    }
  
    
    return tmp_ar;
}
 
// wrapped in windows onload cause
// Firebug 1.1 throws an error otherwise
 
window.onload=function () {
 
console.time('array_reverse')
 
for (var i=10000;i;i--) {
 
array_reverse( [ 'php', '4.0', ['green', 'red'] ], true );
 
}
 
console.timeEnd('array_reverse')
 
 
console.time('array_reverse2')
 
for (var i=10000;i;i--) {
 
array_reverse2( [ 'php', '4.0', ['green', 'red'] ], true );
 
}
 
console.timeEnd('array_reverse2')
 
}