package Specio::Constraint::Structurable;
use strict;
use warnings;
our $VERSION = '0.45';
use Carp qw( confess );
use Role::Tiny::With;
use Scalar::Util qw( blessed );
use Specio::DeclaredAt;
use Specio::OO;
use Specio::Constraint::Structured;
use Specio::TypeChecks qw( does_role isa_class );
use Specio::Constraint::Role::Interface;
with 'Specio::Constraint::Role::Interface';
{
## no critic (Subroutines::ProtectPrivateSubs)
my $role_attrs = Specio::Constraint::Role::Interface::_attrs();
## use critic
my $attrs = {
%{$role_attrs},
_parameterization_args_builder => {
isa => 'CodeRef',
init_arg => 'parameterization_args_builder',
required => 1,
},
_name_builder => {
isa => 'CodeRef',
init_arg => 'name_builder',
required => 1,
},
_structured_constraint_generator => {
isa => 'CodeRef',
init_arg => 'structured_constraint_generator',
predicate => '_has_structured_constraint_generator',
},
_structured_inline_generator => {
isa => 'CodeRef',
init_arg => 'structured_inline_generator',
predicate => '_has_structured_inline_generator',
},
};
## no critic (Subroutines::ProhibitUnusedPrivateSubroutines)
sub _attrs {
return $attrs;
}
}
sub BUILD {
my $self = shift;
if ( $self->_has_constraint ) {
die
'A structurable constraint with a constraint parameter must also have a structured_constraint_generator'
unless $self->_has_structured_constraint_generator;
}
if ( $self->_has_inline_generator ) {
die
'A structurable constraint with an inline_generator parameter must also have a structured_inline_generator'
unless $self->_has_structured_inline_generator;
}
return;
}
sub parameterize {
my $self = shift;
my %args = @_;
my $declared_at = $args{declared_at};
if ($declared_at) {
isa_class( $declared_at, 'Specio::DeclaredAt' )
or confess
q{The "declared_at" parameter passed to ->parameterize must be a Specio::DeclaredAt object};
}
my %parameters
= $self->_parameterization_args_builder->( $self, $args{of} );
$declared_at = Specio::DeclaredAt->new_from_caller(1)
unless defined $declared_at;
my %new_p = (
parent => $self,
parameters => \%parameters,
declared_at => $declared_at,
name => $self->_name_builder->( $self, \%parameters ),
);
if ( $self->_has_structured_constraint_generator ) {
$new_p{constraint}
= $self->_structured_constraint_generator->(%parameters);
}
else {
for my $p (
grep {
blessed($_)
&& does_role('Specio::Constraint::Role::Interface')
} values %parameters
) {
confess
q{Any type objects passed to ->parameterize must be inlinable constraints if the structurable type has an inline_generator}
unless $p->can_be_inlined;
}
my $ig = $self->_structured_inline_generator;
$new_p{inline_generator}
= sub { $ig->( shift, shift, %parameters, @_ ) };
}
return Specio::Constraint::Structured->new(%new_p);
}
## no critic (Subroutines::ProhibitUnusedPrivateSubroutines)
sub _name_or_anon {
return $_[1]->_has_name ? $_[1]->name : 'ANON';
}
## use critic
__PACKAGE__->_ooify;
1;
# ABSTRACT: A class which represents structurable constraints
__END__
=pod
=encoding UTF-8
=head1 NAME
Specio::Constraint::Structurable - A class which represents structurable constraints
=head1 VERSION
version 0.45
=head1 SYNOPSIS
my $tuple = t('Tuple');
my $tuple_of_str_int = $tuple->parameterize( of => [ t('Str'), t('Int') ] );
=head1 DESCRIPTION
This class implements the API for structurable types like C<Dict>, C<Map>< and
C<Tuple>.
=for Pod::Coverage BUILD
=head1 API
This class implements the same API as L<Specio::Constraint::Simple>, with a few
additions.
=head2 Specio::Constraint::Structurable->new(...)
This class's constructor accepts two additional parameters:
=over 4
=item * parameterization_args_builder
This is a subroutine that takes the values passed to C<of> and returns a hash
of named arguments. These arguments will then be passed into the
C<structured_constraint_generator> or C<structured_inline_generator>.
This should also do argument checking to make sure that the argument passed
are valid. For example, the C<Tuple> type turns the arrayref passed to C<of>
into a hash, along the way checking that the caller did not do things like
interleave optional and required elements or mix optional and slurpy together
in the definition.
This parameter is required.
=item * name_builder
This is a subroutine that is called to generate a name for the structured type
when it is created. This will be called as a method on the
C<Specio::Constraint::Structurable> object. It will be passed the hash of
arguments returned by the C<parameterization_args_builder>.
This parameter is required.
=item * structured_constraint_generator
This is a subroutine that generates a new constraint subroutine when the type
is structured.
It will be called as a method on the type and will be passed the hash of
arguments returned by the C<parameterization_args_builder>.
This parameter is mutually exclusive with the C<structured_inline_generator>
parameter.
This parameter or the C<structured_inline_generator> parameter is required.
=item * structured_inline_generator
This is a subroutine that generates a new inline generator subroutine when the
type is structured.
It will be called as a method on the L<Specio::Constraint::Structured> object
when that object needs to generate an inline constraint. It will receive the
type parameter as the first argument and the variable name as a string as the
second.
The remaining arguments will be the parameter hash returned by the
C<parameterization_args_builder>.
This probably seems fairly confusing, so looking at the examples in the
L<Specio::Library::Structured::*> code may be helpful.
This parameter is mutually exclusive with the
C<structured_constraint_generator> parameter.
This parameter or the C<structured_constraint_generator> parameter is
required.
=back
=head2 $type->parameterize(...)
This method takes two arguments. The C<of> argument should be an object which
does the L<Specio::Constraint::Role::Interface> role, and is required.
The other argument, C<declared_at>, is optional. If it is not given, then a
new L<Specio::DeclaredAt> object is creating using a call stack depth of 1.
This method returns a new L<Specio::Constraint::Structured> object.
=head1 SUPPORT
Bugs may be submitted at L<https://github.com/houseabsolute/Specio/issues>.
I am also usually active on IRC as 'autarch' on C<irc://irc.perl.org>.
=head1 SOURCE
The source code repository for Specio can be found at L<https://github.com/houseabsolute/Specio>.
=head1 AUTHOR
Dave Rolsky <autarch@urth.org>
=head1 COPYRIGHT AND LICENSE
This software is Copyright (c) 2012 - 2019 by Dave Rolsky.
This is free software, licensed under:
The Artistic License 2.0 (GPL Compatible)
The full text of the license can be found in the
F<LICENSE> file included with this distribution.
=cut