Mastering Modern Perl: Writing Efficient and Maintainable Code/

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Implicit Ideas: The Default Array Variables

Implicit Ideas: The Default Array Variables

Learn about the default array variables in Perl.

We'll cover the following...

Function arguments array: @_

Perl provides two implicit array variables. Perl passes arguments to functions in an array named @_. Array operations inside functions use this array by default. These two snippets of code are equivalent:

sub foo {
    my $arg = shift;
    ...
}

Just as $_ corresponds to the pronoun “it,” @_ corresponds to the pronouns “they” and “them.” Unlike $_, each function has a separate copy of @_. The built-ins shift and pop operate on @_, if provided no explicit operands.

Command-line arguments array:

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