What are the uses of an underscore in Haxe?

Question

What are the uses of the underscore in Haxe?

I see that I can use it in loops and in array and map comprehensions when I don't care what the counter is, for example:

var a = [for (_ in 0...5) Math.random()]; // 5 random nums

Are there any other places where it's commonly used?

Answer 1

It's generally to denote values that indeed exist, but are not used in the code. Other uses would include:

1. function arguments that are not used:

   button.addListener('click', function (_) trace('clicked!'));
   

2. enum constructor arguments that are ignored:

   var o = haxe.ds.Option.Some(5);
   switch o {
     case None: trace('no value');
     case Some(_): trace('some value');
   }