Variable number of args in js, passing from function to function, manipulating, etc.

args.js

#!/usr/bin/env node
// Shows how to manipulate variable number of arguments, passing them
// around, etc.

// To just pass a variable number of arguments along, do this. This can be
// useful in a constructor, to pass the args to an init function, for example.
function passArgs() {
  done.apply(this, arguments);
}

// To manipulate the list before passing it along, first turn it into an
// array.
function prependArg() {
  var args = Array.prototype.slice.call(arguments);
  args.unshift('(he said)');
  done.apply(this, args);
}

// Same, but a slightly different manipulation
function pushArg() {
  var args = Array.prototype.slice.call(arguments);
  args.push("again!");
  done.apply(this, args);  
}

// This is just a wrapper for console.log. Again, passing args along ...
function done() {
  console.log.apply(console, arguments);
}

// Try them out:
passArgs('and', 'now');
prependArg('for', 'something');
pushArg('completely', 'different');

// Output:
// > and now
// > (he said) for something
// > completely different again!

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