javascript: optional first argument in function

Question

I have a typical javascript function with some parameters

my_function = function(content, options) { action } 

if I call the function as such :

my_function (options) 

the argument "options" is passed as "content"

how do i go around this so I can either have both arguments passed or just one ? thank you

Answer 1

You have to decide as which parameter you want to treat a single argument. You cannot treat it as both, content and options.

I see two possibilities:

1. Either change the order of your arguments, i.e. function(options, content)

2. Check whether options is defined:

   function(content, options) {     if(typeof options === "undefined") {         options = content;         content = null;     }     //action } 

   But then you have to document properly, what happens if you only pass one argument to the function, as this is not immediately clear by looking at the signature.

Answer 2

my_function = function(hash) { /* use hash.options and hash.content */ }; 

and then call:

my_function ({ options: options }); my_function ({ options: options, content: content });