sub greet {
    my $name = shift;
    print "Hello, $name\n";
}

greet('dev2000');

[download]

In mod_perl, with Apache::Registry, your script is cached in a sub, and that sub gets the Apache object as its argument. You could of course write this: 

$_[0]->send_http_header('text/plain');
$_[0]->print("mod_perl rules!\n");

[download]
But it's easier to have a named variable for that, especially when you use other subs and your @_ gets overwritten.

Back to the point, your script: 
my $r = shift;
...

[download]
is wrapped in a sub so it can be cached: 
package Some::URL::Based::Package::Name;use Apache qw(exit);sub handle
+r {
#line 1 script.pl
my $r = shift;
...

}

[download]
And suddenly, it all makes sense. 

- Yes, I reinvent wheels.
- Spam: Visit eurotraQ.

In reply to Re: Re: Re: what does shift do? by Juerd
in thread what does shift do? by dev2000

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