var sanitize = require("sanitize-arguments");
function Person(name, birthdate, size, pets, ability) {
  var args = sanitize(arguments, Person, [String, Date, Number, Array, Function]);
  
  // Now we can be sure that all arguments are in the right order
  this.properties = {
    name: args.name,
    birthdate: args.birthdate,
    size: args.size,
    pets: args.pets,
    ability: args.ability
  };
  
  console.log(this.properties);
}
// Even if someone totally fucks up the order and leaves out some arguments
new Person("silvinci", 180, ["dog", "cat"]);
// we still get the right order:
// { name: "silvinci", size: 180, pets: ["dog", "cat"], birthdate: undefined, ability: undefined }

Just grab it with the awesome npm.

$ npm install sanitize-arguments

Or clone the repository.

$ git clone git://github.com/silvinci/node-sanitize-arguments

There are two ways of using sanitize. The example above shows the first (and prefered) one. The first argument is your arguments object, which contains all supplied values passed to the function. The second one is the Function itself. The third one is an Array of Types or Objects indicating the desired order. It's similiar to Java's function(String name, Date birthdate, ...). We just take our "strong types" out of the warehouse and put them into sanitize.

When giving these three arguments to sanitize it will return an object where all the values are paired with their correct variable name and undefined values stay undefined, like so:

{
  name: "silvinci",
  birthdate: undefined,
  size: 180,
  pets: ["dog", "cat"],
  ability: undefined
}

It also effectively changes the arguments object, thus altering the function's variables aswell. But this doesn't work in every case. First of all: This won't work in strict mode, because the magic link between arguments and its variables is disabled. You also have to make sure that you always apply the full count of arguments when calling your function, since only defined variables can be changed via arguments.

Only when you can be sure, that you're code won't ever run in strict mode and your function always gets called with the full count of arguments, that may be swapt, then you can use sanitize in another, even more comfortable way.

function test(a, b, c, d, e)
  sanitize(arguments, [String, Date, Number, Array, Function]);
  console.log(a, b, c, d, e);
}

Using the magic link the variables are changed and you don't have to use the returned object. Please note, that sanitize will still return an object: the altered arguments so you could acces the arguments by returned[0] too.

sanitize comes with some extra sugar for you. It exposes the typechecks it uses itself.

• typeOf(object) is a typeof like you would expect it to be. For instance typeOf([]) returns "Array" and not "object", like 'typeof []' does.
• nameOf(Function) returns a function's name. Useful for passed in functions.
• argsOf(Function) returns an array of the expected arguments.

I happily accept pull requests and work on issues!

• jbrumwell

(The MIT License)

Copyright (c) 2012 Jan Buschtöns <buschtoens@gmail.com>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the 'Software'), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

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