From: Robert Klemme <shortcutter@...>
Date: 2012-02-10T21:59:40+09:00
Subject: Re: How does && work in ruby

On Fri, Feb 10, 2012 at 1:18 PM, Phil Carter <pcarter42@gmail.com> wrote:
> Brilliant! That really helps, the bit I was missing is that it returns
> the last operand if both are truthy, not immediately obvious.

There is also Enumerable#all? which works similarly (i.e. short
circuit) but will evaluate the block as criterion:

irb(main):010:0> e = [1,2,3]
=> [1, 2, 3]
irb(main):011:0> e.all? {|x| x > 0}
=> true
irb(main):012:0> e.all? {|x| p x; x > 0}
1
2
3
=> true
irb(main):013:0> e.all? {|x| x > 1}
=> false
irb(main):014:0> e.all? {|x| p x; x > 1}
1
=> false

There's also Enumerable#any? which has OR logic.

irb(main):018:0> e.any? {|x| p x;x > 1}
1
2
=> true

Kind regards

robert


-- 
remember.guy do |as, often| as.you_can - without end
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