From: Dermot <[EMAIL PROTECTED]>
> 2008/12/5 Raymond Wan <[EMAIL PROTECTED]>:
> > Maybe I have missed something, but it sounds like you want something like
> > [NB: This is not Perl code, but sort of pseudocode]:
> >
> > if (defined (title1)) {
> > $title = title1;
> > }
> > elsif (defined (title2)) {
> > $title = title2;
> > }
> > else {
> > $title = oldtitle;
> > }
> >
> > Is this correct? If so, the ? operator is not what you want. What the
> > operator does is this. For "a ? b : c" it does the test on "a" but not on
> > "b". All it does is say, "Is 'a' true? If so, return 'b'. Otherwise,
> > return 'c'." You aren't doing any test on b, but it sounds like you want
> > to? (Sorry, you showed your table, but you didn't quite explain what
> > title1, title2, and oldtitle means -- so, I am guessing here that you also
> > want to test title2? I am also assuming that you do not want either title1
> > or title2, but would prefer title1 -- hence the order of the pseudocode
> > above.)
>
>
> Your right.
>
> I was looking to test title1 and return that if it was defined else,
> test title2 and return that if defined, failing that, return oldtitle.
> The ? : operator won't do that. It tests title1 and if true returns
> title2. That would not be what I was after!
Do you insist on the "defined"? I mean what if title1 is an empty
string instead? Or zero? If you do not mind we treat those two as an
undef them
$title = $title1 || $title2 || $old_title;
is enough.
In Perl 5.10 there is a new operator // that tests the defined()ness
so there you could write
$title = $title1 // $title2 // $old_title;
and it would mean exactly what you said you need. It will set $title
to $title1 if defined, otherwise to $title2 if defined and otherwise
to $old_title.
HTH, Jenda
===== [EMAIL PROTECTED] === http://Jenda.Krynicky.cz =====
When it comes to wine, women and song, wizards are allowed
to get drunk and croon as much as they like.
-- Terry Pratchett in Sourcery
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