Hi Andriano, Thank you very much,
Li --- Adriano Ferreira <[EMAIL PROTECTED]> wrote: > On 9/28/06, chen li <[EMAIL PROTECTED]> wrote: > > Hi all, > > > > I write a small script for permutation. When I use > > version 1) Perl always complaint it although I get > the > > result. If I use version 2) it never says a word > about > > it. Any comments? > > Perl always complain (provided you called for that > with -w or "use > warnings") when you do something like that: > > $ perl -w -e 'my $a; $a' > Useless use of a variable in void context at -e line > 1 > > This is meant to warn you about a probable mistake: > you may have meant > $a++ > a # to invoke a sub > or something like that. As Igor has said the first > statement in the > for is often used for declaring loop variables or, > more generally, for > loop initialization statements. If you don't have > these initialization > statements, you may omit it. > > Regards, > Adriano Ferreira > > -- > To unsubscribe, e-mail: > [EMAIL PROTECTED] > For additional commands, e-mail: > [EMAIL PROTECTED] > <http://learn.perl.org/> > <http://learn.perl.org/first-response> > > > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] <http://learn.perl.org/> <http://learn.perl.org/first-response>
