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59 lines
1.3 KiB
Plaintext
59 lines
1.3 KiB
Plaintext
# The reserved word 'sub' defines a subroutine.
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# Basic subroutine with on parameter:
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sub mysub {
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my $param = shift;
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#
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# Do stuff here
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return $myvalue
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}
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$x = mysub( "value" )
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# Named parameters to subroutines:
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sub named_params_example {
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my ( $arg ) = @_;
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# Use my ( $self, $arg ) = @_; if you are in object land.
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#
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say $arg->{one};
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say $arg->{two};
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}
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#
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# Calling the above subroutine:
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named_params_example({
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one => "First argument",
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two => "Second argument"
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});
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# Named parameters with default values:
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sub named_params_with_defaults {
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my ( $arg ) = @_;
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# Use my ( $self, $arg ) = @_; if you are in object land.
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#
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# Set defaults
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# If option given Use options Else
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my $one = exists $arg->{one} ? $arg->{one} : "default1";
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my $two = exists $arg->{two} ? $arg->{two} : "default2";
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}
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#
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named_params_with_defaults({ one => "override arg 'one'" });
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# Return named params from a subroutine:
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sub foo {
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my $clause = 'This is a clause';
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my @param = qw/ one two thee /;
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return ({
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clause => $clause,
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params => \@param
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});
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}
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#
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my $r = foo();
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#
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say "clause = [$r->{clause}]";
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for my $p ( @{ $r->{params} } ) {
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say "param = [$p]";
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}
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# More help with Perl's fabulous perldoc command:
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perldoc sub
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