Scott: Created page with '== Define == sub hypotenuse { return sqrt( ($_[0] 2) + ($_[1] 2) ); # "return" is optional } sub print_name_and_age { my ($name, $age) = @_; …'

2011-02-01T18:21:01Z

Created page with '== Define == <source lang="perl"> sub hypotenuse { return sqrt( ($_[0] ** 2) + ($_[1] ** 2) ); # "return" is optional } sub print_name_and_age { my ($name, $age) = @_; …'

New page

== Define ==
<source lang="perl">
sub hypotenuse {
return sqrt( ($_[0] ** 2) + ($_[1] ** 2) ); # "return" is optional
}
sub print_name_and_age {
my ($name, $age) = @_; # @_ is the calling context array
print "$name is $age years old.\n";
my $same_name = $_[0]; # first arg of @_ array
}
</source>

== Call ==
<source lang="perl">
$diag = hypotenuse(3,4); # $diag is 5
$diag = &hypotenuse(3,4); # the & is optional
print_name_and_age("Lassie", 3); # @_ defined to be ("Lassie", 3)
</source>

== Required arguments ==
Change the first line above to
<source lang="perl">
sub print_name_and_age($$) {
</source>
to require two scalar arguments.

== Passing arrays and hashes ==
Use references to operate on the passed data
<source lang="perl">
sub my_function($$){
my %hash = %{$_[0]};
my @array = @{$_[1]};
...
}
my_function(\%the_hash, \@the_array);
</source>
A subroutine may return an array or hash, too.

Perl Subroutines - Revision history

Scott: Created page with '== Define == sub hypotenuse { return sqrt( ($_[0] ** 2) + ($_[1] ** 2) ); # "return" is optional } sub print_name_and_age { my ($name, $age) = @_; …'

Scott: Created page with '== Define == sub hypotenuse { return sqrt( ($_[0] 2) + ($_[1] 2) ); # "return" is optional } sub print_name_and_age { my ($name, $age) = @_; …'