I would tend to turn that statement around and say that if your code relies on $_ at a higher level, and clobbering it at a lower level results in chaos, then you shouldn't be using $_ at the higher level.

It is not that easy. Clobering $_ at a lower level can easily break map, for/foreach and grep constructs at a higher level as shown at this topic: while(<>) { ... } considered harmful.

In short: would you rewrite code like

my @result = map some_sub($_), qw(a b c d);

[download]

to

my @result = map { my $x = $_; local $_; some_sub($x) } qw(a b c d);

[download]

to satisfy your requirement?

--
Ilya Martynov, ilya@iponweb.net
CTO IPonWEB (UK) Ltd
Quality Perl Programming and Unix Support UK managed @ offshore prices - http://www.iponweb.net
Personal website - http://martynov.org

In reply to Re: Re: Using $_ as a temp var, especially in functions by IlyaM
in thread Using $_ as a temp var, especially in functions by BUU

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