function trim (str, charlist) {
    // http://kevin.vanzonneveld.net
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   improved by: mdsjack (http://www.mdsjack.bo.it)
    // +   improved by: Alexander Ermolaev (http://snippets.dzone.com/user/AlexanderErmolaev)
    // +      input by: Erkekjetter
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +      input by: DxGx
    // +   improved by: Steven Levithan (http://blog.stevenlevithan.com)
    // +    tweaked by: Jack
    // +   bugfixed by: Onno Marsman
    // *     example 1: trim('    Kevin van Zonneveld    ');
    // *     returns 1: 'Kevin van Zonneveld'
    // *     example 2: trim('Hello World', 'Hdle');
    // *     returns 2: 'o Wor'
    // *     example 3: trim(16, 1);
    // *     returns 3: 6
 
    var whitespace, l = 0, i = 0;
    str += '';
    
    if (!charlist) {
        // default list
        whitespace = " \n\r\t\f\x0b\xa0\u2000\u2001\u2002\u2003\u2004\u2005\u2006\u2007\u2008\u2009\u200a\u200b\u2028\u2029\u3000";
    } else {
        // preg_quote custom list
        charlist += '';
        whitespace = charlist.replace(/([\[\]\(\)\.\?\/\*\{\}\+\$\^\:])/g, '$1');
    }
    
    l = str.length;
    for (i = 0; i < l; i++) {
        if (whitespace.indexOf(str.charAt(i)) === -1) {
            str = str.substring(i);
            break;
        }
    }
    
    l = str.length;
    for (i = l - 1; i >= 0; i--) {
        if (whitespace.indexOf(str.charAt(i)) === -1) {
            str = str.substring(0, i + 1);
            break;
        }
    }
    
    return whitespace.indexOf(str.charAt(0)) === -1 ? str : '';
}

function strrpos( haystack, needle, offset){
    // http://kevin.vanzonneveld.net
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   bugfixed by: Onno Marsman
    // *     example 1: strrpos('Kevin van Zonneveld', 'e');
    // *     returns 1: 16
 
    var i = (haystack+'').lastIndexOf( needle, offset ); // returns -1
    return i >= 0 ? i : false;
}

function array_merge() {
    // http://kevin.vanzonneveld.net
    // +   original by: Brett Zamir (http://brettz9.blogspot.com)
    // +   bugfixed by: Nate
    // -    depends on: is_int
    // %          note: Relies on is_int because !isNaN accepts floats     
    // *     example 1: arr1 = {"color": "red", 0: 2, 1: 4}
    // *     example 1: arr2 = {0: "a", 1: "b", "color": "green", "shape": "trapezoid", 2: 4}
    // *     example 1: array_merge(arr1, arr2)
    // *     returns 1: {"color": "green", 0: 2, 1: 4, 2: "a", 3: "b", "shape": "trapezoid", 4: 4}
    // *     example 2: arr1 = []
    // *     example 2: arr2 = {1: "data"}
    // *     example 2: array_merge(arr1, arr2)
    // *     returns 2: {1: "data"}
    
    var args = Array.prototype.slice.call(arguments);
    var retObj = {}, k, j = 0, i = 0;
    var retArr;
    
    for (i=0, retArr=true; i < args.length; i++) {
        if (!(args[i] instanceof Array)) {
            retArr=false;
            break;
        }
    }
    
    if (retArr) {
        return args;
    }
    var ct = 0;
    
    for (i=0, ct=0; i < args.length; i++) {
        if (args[i] instanceof Array) {
            for (j=0; j < args[i].length; j++) {
                retObj[ct++] = args[i][j];
            }
        } else {
            for (k in args[i]) {
                if (is_int(k)) {
                    retObj[ct++] = args[i][k];
                } else {
                    retObj[k] = args[i][k];
                }
            }
        }
    }
    
    return retObj;
}

function is_int( mixed_var ) {
    // http://kevin.vanzonneveld.net
    // +   original by: Alex
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +    revised by: Matt Bradley
    // +   bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // %        note 1: 1.0 is simplified to 1 before it can be accessed by the function, this makes
    // %        note 1: it different from the PHP implementation. We can't fix this unfortunately.
    // *     example 1: is_int(23)
    // *     returns 1: true
    // *     example 2: is_int('23')
    // *     returns 2: false
    // *     example 3: is_int(23.5)
    // *     returns 3: false
    // *     example 4: is_int(true)
    // *     returns 4: false
 
    if (typeof mixed_var !== 'number') {
        return false;
    }
 
    if (parseFloat(mixed_var) != parseInt(mixed_var, 10)) {
        return false;
    }
    
    return true;
}

function sort (inputArr, sort_flags) {
    // http://kevin.vanzonneveld.net
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +    revised by: Brett Zamir (http://brettz9.blogspot.com)
    // +   improved by: Brett Zamir (http://brettz9.blogspot.com)
    // %        note 1: SORT_STRING (as well as natsort and natcasesort) might also be
    // %        note 1: integrated into all of these functions by adapting the code at
    // %        note 1: http://sourcefrog.net/projects/natsort/natcompare.js
    // *     example 1: sort(['Kevin', 'van', 'Zonneveld']);
    // *     returns 1: true
    // *     example 2: fruits = {d: 'lemon', a: 'orange', b: 'banana', c: 'apple'};
    // *     example 2: sort(fruits);
    // *     returns 2: true
    // *     results 2: fruits == {0: 'apple', 1: 'banana', 2: 'lemon', 3: 'orange'}
 
    var valArr = [], keyArr=[];
    var k = '', i = 0, sorter = false;
    
    for (k in inputArr) { // Get key and value arrays
        valArr.push(inputArr[k]);
        delete inputArr[k] ;
    }
 
    switch (sort_flags) {
        case 'SORT_STRING': // compare items as strings
            sorter = function (a, b) {
                return strnatcmp(a, b);
            };
            break;
        case 'SORT_LOCALE_STRING': // compare items as strings, based on the current locale (set with  i18n_loc_set_default() as of PHP6)
            sorter = function (a, b) {
                return(a.localeCompare(b));
            };
            break;
        case 'SORT_NUMERIC': // compare items numerically
            sorter = function (a, b) {
                return(a - b);
            };
            break;
        case 'SORT_REGULAR': // compare items normally (don't change types)
        default:
            sorter = function (a, b) {
                if (a > b)
                    return 1;
                if (a < b)
                    return -1;
                return 0;
            };
            break;
    }
    valArr.sort(sorter);
 
    for (i = 0; i < valArr.length; i++) { // Repopulate the old array
        inputArr[i] = valArr[i];
    }
    return true;
}

function in_array(needle, haystack, argStrict) {
    // http://kevin.vanzonneveld.net
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // *     example 1: in_array('van', ['Kevin', 'van', 'Zonneveld']);
    // *     returns 1: true
 
    var found = false, key, strict = !!argStrict;
 
    for (key in haystack) {
        if ((strict && haystack[key] === needle) || (!strict && haystack[key] == needle)) {
            found = true;
            break;
        }
    }
 
    return found;
}

function is_array( mixed_var ) {
    // http://kevin.vanzonneveld.net
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   improved by: Legaev Andrey
    // +   bugfixed by: Cord
    // +   bugfixed by: Manish
    // +   improved by: Onno Marsman
    // %        note 1: In php.js, javascript objects are like php associative arrays, thus JavaScript objects will also
    // %        note 1: return true
    // *     example 1: is_array(['Kevin', 'van', 'Zonneveld']);
    // *     returns 1: true
    // *     example 2: is_array('Kevin van Zonneveld');
    // *     returns 2: false
    // *     example 3: is_array({0: 'Kevin', 1: 'van', 2: 'Zonneveld'});
    // *     returns 3: true
    // *     example 4: is_array(function tmp_a(){this.name = 'Kevin'});
    // *     returns 4: false
 
    var key = '';
 
    if (!mixed_var) {
        return false;
    }
 
    if (typeof mixed_var === 'object') {
 
        if (mixed_var.hasOwnProperty) {
            for (key in mixed_var) {
                // Checks whether the object has the specified property
                // if not, we figure it's not an object in the sense of a php-associative-array.
                if (false === mixed_var.hasOwnProperty(key)) {
                    return false;
                }
            }
        }
 
        // Uncomment to enable strict JavsScript-proof type checking
        // This will not support PHP associative arrays (JavaScript objects), however
        // Read discussion at: http://kevin.vanzonneveld.net/techblog/article/javascript_equivalent_for_phps_is_array/
        //
        //  if (mixed_var.propertyIsEnumerable('length') || typeof mixed_var.length !== 'number') {
        //      return false;
        //  }
 
        return true;
    }
 
    return false;
}