Add to JavaScript function prototype ability to find source in file

gistfile1.js

if(typeof _scriptsRecorded == "undefined"){
    var scriptBodies = {}
    var scripts = document.querySelectorAll("script");
    for(var i = 0, len = scripts.length;i<len;i++){
        var script = scripts[i];
        (function(src){
            $.get(src, function(data){
                scriptBodies[src] = data;
            })
        })(script.src)
    }
}
_scriptsRecorded = true;

Function.prototype.findFile = function(){
    var source = this.toSource();
    for(var key in scriptBodies){
        var script = scriptBodies[key];
        if(script.indexOf(source) > -1){
            return key;
        }
    }
}

Currently this assumes jQuery is present, but I would like to remove that requirement.