Just a quick appendum. Be careful to make a copy of @_ locally if you are manipulating things a bit, eg: 
#!/usr/bin/perl -w
use strict;

my @words = ('These','are','words',"\n");

print "Original: @words";

safesub(@words);

print "After safe sub: @words";

unsafesub(@words);

print "After unsafe sub: @words";

exit(0);

sub safesub {
    print "safesub to uppercase: ";
    my @uppercasewords = @_;
    for (@uppercasewords) {
        tr/a-z/A-Z/;
    }
    print "@uppercasewords";
}

sub unsafesub {
    print "unsafesub to uppercase: ";
    for (@_) {
        tr/a-z/A-Z/;
    }
    print "@_";
}

# output

Original: These are words
safesub to uppercase: THESE ARE WORDS
After safe sub: These are words
unsafesub to uppercase: THESE ARE WORDS
After unsafe sub: THESE ARE WORDS

[download]
Notice how after unsafe sub has been called that @words has changed. If that's not what you're expecting, it can sometimes give you a shock. So unless the sub is very trivial, or you specifically do intend to amend the caller var(s), make sure you make a copy to play with in the sub.

.02

cLive ;-)

--
seek(JOB,$$LA,0);

In reply to Re: (jeffa) Re: Collecting all values with shift by cLive ;-)
in thread [untitled node, ID 193991] by Samn

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