Default function parameter ordering

Question

Reading through this, I came to the bit on default values for function arguments:

fill = (container, liquid = \"coffee\") ->
  \"Filling the #{container} with         


        

Answer 1

Currently, there's no way to call with named arguments. It would require knowing the arguments (names, positions, and/or default values) at the calling site, which is not always feasible in javascript/coffeescript.

Instead if you have many arguments and you want to name them and have default values, you could do something like this:

fill = (opts = {}) ->
    opts.container ?= "mug"
    opts.liquid ?= "coffee"
    "Filling the #{opts.container} with #{opts.liquid}..."

alert fill
    liquid:"juice"
    container:"cup"

alert fill
    liquid:"juice"

alert fill()