Re: Boolean matters

[Philippe Lhoste <PhiLho@...>]

On 04/12/2012 10:38, spir wrote:
> I never have any use for xor in practice. What examples usage do you have? (I really ask,
> i'm interested in knowing when & where we may need it, whether it is worth having it built
> in a prog lang).

I use it sometime (in Java), when I find an expression equivalent to:

if a and not b or b and not a then
...
end

Indeed, the opportunities are scarce...
And I feel the need to explain why I use this ^ symbol here...

Mmm, now that I think of it, a simple

  if (a != b)

can work in Java, if a and b are boolean! (And might be easier to understand at a glance.)

I tend to stay away from boolean comparisons because if (a == true) seems so redundant to 
me (and I often see beginners doing the dreaded if (a = true), the only case where it can 
work in Java!), but here it makes sense.

In languages where some various values can be interpreted as true or false, such 
comparison doesn't work. Well, unless converting them to true booleans, which lead us back 
to the original message! ;-)

--
Philippe Lhoste
--  (near) Paris -- France
--  http://Phi.Lho.free.fr
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