Perl Subroutine aka function

A Perl function (subroutine) is a group of statements. In Perl you can use the terms: subroutine, method and function as you wish.

Define and Call a Subroutine

Perl defines a subroutine like this:

sub perl_subroutine_name{
   body of ...
}

The typical way of calling that Perl subroutine is as follows ?

perl_subroutine_name( list of arguments );

Before Perl 5.0, the syntax for calling subroutines was different:

&subroutine_name( list of arguments );

The old style will work in the newest versions of Perl, but it is not recommended.

Example function definition:

#!/usr/bin/perl
sub perl_hello{
   print "Hello, World!\n";
}

Example function call:

perl_hello();

Output:

Hello, World!