/*
   javascript
   futile attempts to create a generic PHP-JS communications library
   input:  mixed
   output: JSON (as simple as a string)
           "val"    is always the result node
           "error"  is sometimes supplied if there IS an error
*/

function jdx () {
    // javascript data exchange protocol
    // default is POST, but GET works too
    var i; // variable i is locally reused (warn)
    var v = []; // blank val array
    for( var i = 1; i < arguments.length; i++ ) {
        // variable i is locally reused
        v[i-2] = arguments[i]; // transfer params to values
    }
    jQuery.ajax({
        async: false, // !important;
        cache: false, // !important;
        global: false,
        url: ".ajax.php",
        type: "POST", // just cos it has no length limit
        dataType: "json",
        data: ({
            req : arguments[0],
            val : v.join('!!JOIN!!') // meh
        }),
        success: function(data) {
            i = data.val;
        }
    });
    return i;
}




<?php
    /*
       PHP
       futile attempts to create a generic PHP-JS communications library
       input:  REST
       output: JSON (as simple as a string)
    */
    header('Cache-Control: no-cache, must-revalidate');
    header('Expires: Mon, 26 Jul 1997 05:00:00 GMT'); // IE bug: caches JSON
    header('Content-type: application/json'); // you return JSON

    if ($_GET) {
        $args = $_GET; // heh, just giving it a name
    } else {
        $args = $_POST; // POST-compatible?
    }

    $req = $args['req']; // what the client is requesting
    $val = $args['val']; // anything the client wants to specify

    try {
        $ret = @call_user_func_array ($req, explode('!!JOIN!!', $val));
        echo '{"val": "' . $ret . '"}';
    } catch (Exception $e) { // just in case
        echo ('{"val": "",
                "error": ' . $e->getMessage() . '}');
    }
?>