Lightweight standalone jsonP utility (jQuery like)

jsonp.js

window.jsonP = function ( url, callback, paramName ) {
    var self          = arguments.callee                                          // this function
        , queue       = self.queue || ( self.queue = {} )                         // callback queue
        , name        = 'jsonP' + Object.keys( queue ).length  + '_' + Date.now() // unique callback name
        , global      = 'jsonP.queue.' + name                                     // global callback name
        , placeholder = /(=)\?(?=&|$)/                                            // placeholder pattern
        , script      = document.createElement( 'script' )                        // script dom node
    ;
    script.type               = 'text/javascript';
    script.src                = placeholder.test( url ) ?
        url.replace( placeholder, '$1' + global ) :
        url + ( /\?/.test(url) ? '&' : '?' ) + ( paramName || 'callback' ) + '=' + global
    ;
    script.onload             = function () {
        delete queue[name];
    };
    script.onreadystatechange = function() { // IE sucks
        this.readyState == 'complete' && this.onload();
    };
    queue[name]               = callback;
    ( document.getElementsByTagName('head')[0] || document.documentElement ).appendChild( script );
};

jsonp.min.js

window.jsonP=function(a,b,c){var d=arguments.callee,e=d.queue||(d.queue={}),f="jsonP"+Object.keys(e).length+"_"+Date.now(),g="jsonP.queue."+f,h=/(=)\?(?=&|$)/,i=document.createElement("script");i.type="text/javascript",i.src=h.test(a)?a.replace(h,"$1"+g):a+(/\?/.test(a)?"&":"?")+(c||"callback")+"="+g,i.onload=function(){delete e[f]},i.onreadystatechange=function(){"complete"==this.readyState&&this.onload()},e[f]=b,(document.getElementsByTagName("head")[0]||document.documentElement).appendChild(i)};