From: Phrogz <phrogz@...>
Date: 2007-09-11T08:40:06+09:00
Subject: Re: is there a one liner to initialize a variable to 1, or increment by 1?

On Sep 10, 5:25 pm, Summercool <Summercooln...@gmail.com> wrote:
> but let's say if I have a variable i want to increment by 1
> is there an idiomatic and elegant way to say
>
>  foo += 1, unless foo is nil, then set it to 1 ?

Usually I am doing this sort of thing in a Hash or Array, where the
default value is your friend:
  counts = Hash.new(0) # or Array.new(0), depending on need
  ...later...
  counts[ my_var ] += 1

But, to answer your question specifically, I'd probably do a non-one-
liner:
  foo ||= 0
  foo += 1
or (like yours, if I was feeling cheeky):
  foo = foo.nil? ? 1 : foo + 1