JavaScript Tools

tools.js

// Change a function to log arguments and return
function log_args_return(f){
  var s=f.toString(),
  n=f.name,
  _n="_"+n;
  return "function "+n+"(){"+
  s.replace(n,_n)+
  ";console.log('"+n+" args', Array.prototype.slice.call(arguments));"+
  "var r="+_n+".apply(null, arguments);"+
  "console.log('"+n+" return', r);return r}"
}
// The easiest way to use it and recover the value in "_"+function_name
var function_name = "log_args_return";
eval("_$=$;eval(log_args_return($))".replace(/\$/g,function_name))

// Format variables in a string
// "Hello $, my name is $".replaceEach("$", "SOMEONE", "ME")
String.prototype.replaceEach=function (m){var r=this,i=0;while(r.indexOf(m)>=0){r=r.replace(m, arguments[i++])};return r}