Answer: How do I localize $_ in while loops? contributed by ajdelore As discussed here, $_ is automatically localized in a foreach loop. So, for example: foreach (qw/foo bar/) { print; print foreach (qw/one two three/); } # output: fooonetwothreebaronetwothree [download] However, a while loop does not do this automatically: foreach (qw/foo bar/) { print; my @list = qw/one two three/; print while (shift @list); } # output: foofoofoofoobarbarbarbar [download] In order to do this, you need to explicitly localize $_ within the while loop: foreach (qw/foo bar/) { print; my @list = qw/one two three/; print while (local $_ = shift @list); } # output: fooonetwothreebaronetwothree [download] Another way to do it: { local $_; print while (shift @list); } [download] Note that you must have the local declaration enclosed in a block with the while statement, as above. The following example will not work: # will not localize $_ to the while loop local $_; print while (shift @list); [download] See perlop for more information.

Answer: How do I localize $_ in while loops? contributed by Roy Johnson Please note that shift does not populate $_ by default, so ajdelore's "Another way to do it" is not. The assignment still has to be explicit.

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