Re: Duh. 'my' scope in if else blocks.

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Re^2: Duh. 'my' scope in if else blocks. by Thilosophy (Curate) on Dec 11, 2007 at 11:14 UTC
This won't work either, even though `my $t` is outside of the curlies (but inside the parens) now: `if ( my $t = shift ) { $t =~ s/change_something/to_something_else/; } print "$t\n"; # out of scope here` [download] `if` behaves similar to `for` in this respect. Somewhat surprisingly then, this does not work: `print $t if (my $t = shift);` [download]	[reply] [d/l] [select]
Re^3: Duh. 'my' scope in if else blocks. by ikegami (Patriarch) on Dec 11, 2007 at 19:57 UTC
doom's explanation is wrong. It has nothing to do with order. Even if you fixed the order, it still wouldn't work. `(my $t = shift) and print $t; # Fails.` [download] Variables cannot be used (by name) in the statement in which they are declared. This allows statements such as `my $t = $t;` to work. `print $t if (my $t = shift); # Fails. my $t = shift; print $t if $t; # Ok. if (my $t = shift) { print $t; } # Ok.` [download]	[reply] [d/l] [select]
Re^3: Duh. 'my' scope in if else blocks. by doom (Deacon) on Dec 11, 2007 at 19:14 UTC
if behaves similar to for in this respect. Yes good point. I always forget about that, too... sometimes you'd like to have the loop counter defined after the loop is over, but you have to make a special effort to do that. This won't work, for example: `my @list = qw( wuhn tew thuree foah DONE whateva you know); for my $i (0..10) { last if ($list[$i] eq 'DONE'); } print "final index: $i\n";` [download] Somewhat surprisingly then, this does not work: `print $t if (my $t = shift);` [download] Well, I wouldn't say that that's exactly a surprise -- after all, it's a fairly odd thing to do, declaring it's a lexical after you use it... This doesn't work either: `$t = shift; print $t; my $t;` [download]	[reply] [d/l] [select]