From: Brian Candler <B.Candler@...>
Date: 2003-05-28T19:12:40+09:00
Subject: Re: Result of && and 'and'

On Wed, May 28, 2003 at 05:14:56PM +0900, Robert Klemme wrote:
> is it guranteed that && and "and" return the last value if all values
> before that return true? Consider:
> 
> irb(main):015:0> x=0
> 0
> irb(main):016:0> x>0 && x
> false
> irb(main):017:0> x=66
> 66
> irb(main):018:0> x>0 && x
> 66
> 
> Not to be misunderstood: I like this, but I'm not sure whether this is
> guaranteed by the language spec.

I use it a lot in this form:

    a ||= "default"

i.e. 'or' evaluates to the left-hand operand if it's not nil, otherwise it
evaluates to the right-hand operand.

So if it's not guaranteed, then changing it would break a lot of my code :-)

Regards,

Brian.