SPUG: trinary ? operator

Meryll Larkin humbaba9 at yahoo.com
Fri Jan 25 20:06:40 CST 2002


1/25/02

Thanks Daryn,

I was able to get that to work in with both integers
and strings.  You were right, I was trying to do this:

if ($boolean == "y") {
    $boolean = 1;
}
else {
    $boolean = 0;
}

Meryll

--- Daryn Nakhuda <daryn at marinated.org> wrote:
> 
> what are you trying to do exactly?
> 
> what you typed is equivalent to:
> 
> if ($ok) {
>     $a = $b;
> }
> else {
>     $a = $c;
> }
> 
> if you meant to do
> 
> if ($a == $ok) {
>    $something = $b;
> }
> else {
>    $something = $c;
> }
> 
> that'd be 
> 
> $something = ($a == $ok) ? $b : $c;
> 
> 
> 
> 
> On Fri, 25 Jan 2002, Meryll Larkin wrote:
> 
> > 1/25/02
> > 
> > Hi Folks, 
> > 
> > I'm using Active Perl5.005_03 on Windows98 and
> 5.6.1
> > on Windows2000 professional edition and I can't
> get
> > the trinary ? operator to work.  Does anyone have
> any
> > experience with this in Windows?  Does my syntax
> need
> > correcting?
> > 
> > On pg 92 of Programming Perl (2nd Edition) an
> example
> > of the trinary operator is given:
> > 
> > $a = $ok ? $b : $c;
> > 
> > I find if I use this syntax, I get an assignment
> to $b
> > (the "true" choice) because $a = $ok has a single
> =
> > instead of ==.  
> > 
> > If I try to use == I don't get an error, the
> entire
> > line seems to be ignored.  
> > 
> > If I use strings and use "eq" the line is also
> > ignored.
> > 
> > Turning on -w gets me this error:
> > Useless use of private variable in void context.
> > Useless use of private variable in void context.
> > (yes, twice, I assume it refers to $b and $c)
> > 
> > help?
> > 
> > Meryll
> > 
> > 
> > 
> > 
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> 


__________________________________________________
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