Really, I do not recommend explicitly defining the @_ var, but I hope it is just for example purposes.

So in that case.... 

#! /usr/bin/perl -w
use strict;

@_ = qw( Lucy, I'm home! );

sub main {
while(my $d = shift) {
    print "$d\n";
}
}

&main;

[download]

You can use this if it really upsets you.

However, assuming your code is not just an example, why in the world are you using the @_ array??? And if your not explicitly defining something to @_, there should not be a variable to read in the main. The package main should always be called first on program execution, and should have @ARGV, and the variables you assigned (globally...). (Side note, yes, I know other built-ins are there, but these are really the vars he needs to deal with.)

Dont just think of @_, $_, etc, as "default variables", but more as pronouns. "These are as bad as it." Is not a proper sentence, and a worse program. "These are apples, and it is an orange. These cannot compare to it." Now the sentence makes no sense for a reason other than bad grammar.

So from what I can tell, you're doing something you shouldn't, and perl is making you type three more charachters... Whatta language.

What would happen to this: 

#!/usr/bin/perl -w
use strict;

@_ = qw( hello world )
@other = qw( hasta la vista baby )

sub main {
while(my $d = shift) {
    print "$d\n"; # Are we coming or going?
    }
}

&main;

[download]

The code actually reads the @_ array, which it should, but more importantly, you can't tell if you're coming or going just from reading it.

Bad monky...

~Hammy

In reply to Re: @_ the default variable? by HamNRye
in thread @_ the default variable? by Anonymous Monk

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