From: Kyle <kcy5b@...>
Date: 2009-11-16T02:13:35+09:00
Subject: Re: what's ||

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It's the lazy execution boolean or operator

x1 = nil
x2 = [1,2,3]
x3 = [4,5,6]

a = x1 || x2.push(4, 5)
b = x3 || x2.push(6, 7)
# assignment operator version often used to initialize a variable if it 
doesn't already have a value
@var ||= 'something'   
@var ||= 'whatevs'

after wards:
  a == x2 == [1, 2, 3, 4, 5]
  b == x3 == [4, 5, 6]
  @var == 'something'





On Sunday November 15 2009 7:59:31 am duxieweb wrote:
> sorry just was learning ruby so have some low level questions, :)
>
> in this statement:
>
> 1.upto(10) do |c| print c," " end
>
> what's the usage of "| ... |" in ruby? can't easily understand.
>
> Thanks.


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