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NAME

Text::Xslate::Bridge::TypeDeclaration - A Type Validator in Xslate.

SYNOPSIS

my $xslate = Text::Xslate->new(
    module => [ 'Text::Xslate::Bridge::TypeDeclaration' ],
);

# @@ template.tx
# <:- declare(
#   user  => 'Some::Model::User',
#   drink => 'Enum["Cocoa", "Cappuchino", "Tea"]'
# ) -:>
# <: user.name :> is drinking a cup of <: $drink :>.

# Success!
$xslate->render('template.tx', {
    user  => Some::Model::User->new(name => 'pokutuna'),
    drink => 'Cocoa',
});
# Output:
#   pokutuna is drinking a cup of Cocoa.


# A string 'Oil' is not a drink
$xslate->render('template.tx', {
    user  => Some::Model::User->new(name => 'pokutuna'),
    drink => 'Oil',
});
# Output:
#   <pre class="type-declaration-mismatch">
#   Declaration mismatch for `drink`
#     Value "Oil" did not pass type constraint "Enum["Cocoa", "Cappuchino", "Tea"]"
#   </pre>
#   pokutuna is drinking a cup of Oil.

DESCRIPTION

Text::Xslate::Bridge::TypeDeclaration is a type validator module for Text::Xslate templates.

Type validation of this module is base on Type::Tiny.

Type::Tiny type constraints are compatible with Moo, Moose and Mouse.

You can use this even if you do not use these type libraries.

If the library-based type is not found, treats as a class type of the name.

DECLARATIONS

This module looks for a type name that was written in the template from Text::Xslate::Bridge::TypeDeclaration::Registry by default.

The following behaviors can be replaced by specifying the registry in registry_class_name option.

Types::Standard

See Types::Standard.

declare(name => 'Str')
declare(user_ids => 'ArrayRef[Int]')
declare(person_hash => 'Dict[name => Str, age => Int]')

Class-Type

It will be treated as a class type when a type of the given name is not found.

declare(engine => 'Text::Xslate')
declare(visitor => 'Maybe[My::Model::UserAccount]')

Hashref

Hashref is treated as Dict[... slurpy Any].

This is a slurpy match. Less value is error. Extra values are ignored.

declare(account_summary => { name => 'Str', subscriber_count => 'Int', icon => 'My::Image' })
declare(sidebar => { profile => { name => 'Str', followers => 'Int' }, recent_entries => 'ArrayRef[My::Entry]' })

OPTIONS

Text::Xslate->new(
    module => [
        'Text::Xslate::Bridge::TypeDeclaration' => [
            # defaults
            method         => 'declare', # method name to export
            validate       => 1,         # enable validation when truthy
            print          => 1,         # enable printing errors to the output buffer when truthy
            on_mismatch    => 'die',     # error handler ('die', 'warn' or 'none')
            registry_class => undef,     # package name for specifying Type::Registry
        ]
    ]
);

APPENDIX

Disable Validation on Production

Perhaps you want to disable validation in production to prevent spoiling performance on a Plack application.

Text::Xslate->new(
    module => [
        'Text::Xslate::Bridge::TypeDeclaration' => [
            validate => $ENV{PLACK_ENV} ne 'production',
        ],
    ],
);

Use type-declaration-mismatch class name

Highlight by css

.type-declaration-mismatch { color: crimson; }

Lint with Test::WWW::Mechanize

# in subclass of Test::WWW::Mechanize
sub _lint_content_ok {
    my ($self, $desc) = @_;

    if (my $mismatch = $self->scrape_text_by_attr('class', 'type-declaration-mismatch')) {
        $Test::Builder::Test->ok(0, $mismatch);
    };

    return $self->SUPER::_lint_content_ok($desc);
}

SEE ALSO

Text::Xslate, Text::Xslate::Bridge

Type::Tiny, Types::Standard, Type::Registry

Smart::Args, Test::WWW::Mechanize

LICENSE

Copyright (C) pokutuna.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

AUTHOR

pokutuna <popopopopokutuna@gmail.com>