preventing multiple parameters from having the same name is an antifeature

[olleicua]

the following produces an error

foo = (_, _, _, bar) ->
  bar * 2

console.log(foo 1,2,3,4)

error: multiple parameters named '_'

In JavaScript you can do:

var foo = function(_, _, _, bar) {
  return bar * 2
}

console.log(foo(1,2,3,4))

which properly logs:

8

This can be very useful when dealing with apis that provide parameters that aren't needed. The default behavior in JS simply assigns overwrites the repeated variable with the last parameter it is bound to. This is a feature of JavaScript and a bug in CoffeeScript.

[vendethiel]

#1002