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NAME

MooseX::Extended::Manual::Includes - An overview of MooseX::Extended optional features

VERSION

version 0.35

includes

Some experimental features are useful, but might not be quite what you want.

By default, MooseX::Extended tries to be relatively conservative. However, you might want to turn it up to 11. There are optional, EXPERIMENTAL features you can use for this. They're turned by the includes flag.

method

    package My::Names {
        use MooseX::Extended types => [qw(compile NonEmptyStr Str )],
          includes                 => 'method';

        param _name => ( isa => NonEmptyStr, init_arg => 'name' );
        param title => ( isa => Str, required => 0, predicate => 1 );

        method name() {
            my $title = $self->title; # $self is injected for you
            my $name  = $self->_name;
            return $title ? "$title $name" : $name;
        }
    }

Adds a method keyword and injects $self into the method body. Requires Function::Parameters.

Note: this is equivalent to writing:

    use Function::Parameters 'method';

The other features of Function::Parameters are not available by default, but see "Fine-Tuning Your Includes" below.

This feature does not work with the optional multi keyword. Thus, if you do this:

    use MooseX::Extended includes => [qw/multi method/];

You cannot do multi method. You'll have to fall back to multi sub.

multi

    use MooseX::Extended includes => 'multi';

    multi sub foo ($self, $x)      { ... }
    multi sub foo ($self, $x, $y ) { ... }

Note: this is equivalent to writing:

    use Syntax::Keyword::MultiSub;

Allows you to redeclare a method (or subroutine) and the dispatch will use the number of arguments to determine which subroutine to use. Note that "slurpy" arguments such as arrays or hashes will take precedence over scalars if they are declared first:

    multi sub foo ($self, @x) { ... }
    multi sub foo ($self, $x) { ... } # will never be called

Thus, the following probably doesn't do what you want.

    package Foo {
        use MooseX::Extended includes => 'multi';

        multi sub foo ($self, @bar) { return '@bar' }
        multi sub foo ($self, $bar) { return '$bar' }
    }

    say +Foo->new->foo(1);
    say +Foo->new->foo(1,2,3);

Both of the above will print the string @bar. The second definition of foo is effectively lost.

You must declare slurpy methods last for them to work correctly:

        multi sub foo ($self, $bar) { return '$bar' }
        multi sub foo ($self, @bar) { return '@bar' }

See https://rt.cpan.org/Ticket/Display.html?id=144171 for more information.

Only available on Perl v5.26.0 or higher. Requires Syntax::Keyword::MultiSub.

This feature does not work with the optional method keyword. Thus, if you do this:

    use MooseX::Extended includes => [qw/multi method/];

You cannot do multi method. You'll have to fall back to multi sub.

async

    package My::Thing {
        use MooseX::Extended
            types    => 'Str',
            includes => 'async';
        use IO::Async::Loop;

        field output => ( is => 'rw', isa => Str, default => '' );

        async sub doit ( $self, @list ) {
            my $loop = IO::Async::Loop->new;
            $self->output('> ');
            foreach my $item (@list) {
                await $loop->delay_future( after => 0.01 );
                $self->output( $self->output . "$item " );
            }
        }
    }

Note: this is equivalent to writing:

    use Future::AsyncAwait;

Allows you to write asynchronous code with async and await.

Only available on Perl v5.26.0 or higher. Requires Future::AsyncAwait.

try

    package My::Try {
        use MooseX::Extended includes => 'try';

        sub reciprocal ( $self, $num ) {
            try {
                return 1 / $num;
            }
            catch ($e) {
                croak "Could not calculate reciprocal of $num: $e";
            }
        }
    }

Note: this is equivalent to writing:

    use Syntax::Keyword::Try;

Allows you to use try/catch blocks, via Syntax::Keyword::Try.

Only available on Perl v5.24.0 or higher. Requires Syntax::Keyword::Try.

If you have Perl v5.35.8 or above, Syntax::Keyword::Try is not loaded and instead we use the native try syntax available in Perl.

Fine-Tuning Your Includes

Some of the features rely on modules that are customizable via import lists when you use them. Instead of accepting our defaults, you can pass your own by passing a hashref to includes. Each key must be the name of a feature you can include and each value must be undef or an array reference that will be expaned to an import list for the module:

    package My::Import::List {
        use MooseX::Extended types => 'is_PositiveOrZeroInt',
          includes                 => {
              method => [qw/method fun/],
              try    => undef,
          };
        use List::Util 'sum';

        method fac($n) { return _fac($n) }

        fun _fac($n) {
            is_PositiveOrZeroInt($n) or die "Don't do that!";
            return 1 if $n < 2;
            return $n * _fac $n - 1;
        }
    }

The above would be equivalentt to writing:

    use Function::Parameters qw(method fun);
    use Syntax::Keyword::Try;

See the underlying module providing each feature to understand what arguments you can pass to the import lists.

AUTHOR

Curtis "Ovid" Poe <curtis.poe@gmail.com>

COPYRIGHT AND LICENSE

This software is Copyright (c) 2022 by Curtis "Ovid" Poe.

This is free software, licensed under:

  The Artistic License 2.0 (GPL Compatible)