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Re: When is $_ local and when is it not?

by converter (Priest)
on Jul 13, 2001 at 17:14 UTC ( #96376=note: print w/replies, xml ) Need Help??


in reply to When is $_ local and when is it not?

The perlsyn manpage documents localization:

In the Foreach loops section:

The foreach loop iterates over a normal list value and sets the variable VAR to be each element of the list in turn. If the variable is preceded with the keyword my, then it is lexically scoped, and is therefore visible only within the loop. Otherwise, the variable is implicitly local to the loop and regains its former value upon exiting the loop.

The Compound statements section of the perlsyn manpage for Perl 5.6.1 (the PM perlsyn doesn't include this) mentions:

Unlike a "foreach" statement, a "while" statement never implicitly localises any variables.

Hope this helps.

  • Comment on Re: When is $_ local and when is it not?

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[Lady_Aleena]: shmem, I already have the plugin installed, just not active.
[shmem]: if you have 1 optional argument, place that at the end of the list. If you have more, go for named parameters.
[Lady_Aleena]: 1 manditory, 2 optional.
[Discipulus]: my ($need,$opta,$optb ) = @_; .. if $opta..
[shmem]: all else leads to trouble, even if the third argument depends on the existence of the second. That may become brittle.
[Discipulus]: but if have case like subname(15,undef,3 ) maybe bettere named parameters
[Lady_Aleena]: I don't want to have to do: alpha_menu($hash, undef, $type);
[Lady_Aleena]: Or what Discipulus said.
[shmem]: Lady_Aleena: geany supports ctags.
[Discipulus]: a good compromise can be my ($need, $opts_ref) = @_ a scalar and an hash reference

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