Re^3: <STDIN> not initializing $

Update: Ignore this post. I read "and a" instead of "from a".

It is added when the while/until condition is a scalar assignment

As far as I can tell, that's not true. The following prints nothing:

perl -le"while ($a=0) { print 'ysth is right'; last }"
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Tested with Perl 5.6.0, 5.6.1, 5.8.0, 5.8.8, 5.10.0.

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Re^4: <STDIN> not initializing $_ by stiller (Friar) on May 01, 2008 at 05:39 UTC
An extra edge case: `perl -le'while($a = 0){print "$a ok\n"; last }' # perl -le'while($a = 1){print "$a ok\n"; last }' # prints 1 ok` [download] But the "implicit test for defined" is built into the `while( )` by language design, there is no extra magic about that in any context?	[reply] [d/l] [select]
Re^4: <STDIN> not initializing $_ by mscharrer (Hermit) on May 01, 2008 at 07:33 UTC
You missed the most important part of the quote: It is added when the while/until condition is a scalar assignment .. from a <>, readline, glob, readdir, or each* operation.* The implicit defined is not added for normal scalar assignments.	[reply]