package Moose::Meta::TypeConstraint;
BEGIN {
$Moose::Meta::TypeConstraint::AUTHORITY = 'cpan:STEVAN';
}
{
$Moose::Meta::TypeConstraint::VERSION = '2.0604';
}
use strict;
use warnings;
use metaclass;
use overload '0+' => sub { refaddr(shift) }, # id an object
'""' => sub { shift->name }, # stringify to tc name
bool => sub { 1 },
fallback => 1;
use Carp qw(confess);
use Class::Load qw(load_class);
use Eval::Closure;
use Scalar::Util qw(blessed refaddr);
use Sub::Name qw(subname);
use Try::Tiny;
use base qw(Class::MOP::Object);
__PACKAGE__->meta->add_attribute('name' => (
reader => 'name',
Class::MOP::_definition_context(),
));
__PACKAGE__->meta->add_attribute('parent' => (
reader => 'parent',
predicate => 'has_parent',
Class::MOP::_definition_context(),
));
my $null_constraint = sub { 1 };
__PACKAGE__->meta->add_attribute('constraint' => (
reader => 'constraint',
writer => '_set_constraint',
default => sub { $null_constraint },
Class::MOP::_definition_context(),
));
__PACKAGE__->meta->add_attribute('message' => (
accessor => 'message',
predicate => 'has_message',
Class::MOP::_definition_context(),
));
__PACKAGE__->meta->add_attribute('_default_message' => (
accessor => '_default_message',
Class::MOP::_definition_context(),
));
# can't make this a default because it has to close over the type name, and
# cmop attributes don't have lazy
my $_default_message_generator = sub {
my $name = shift;
sub {
my $value = shift;
# have to load it late like this, since it uses Moose itself
my $can_partialdump = try {
# versions prior to 0.14 had a potential infinite loop bug
load_class('Devel::PartialDump', { -version => 0.14 });
1;
};
if ($can_partialdump) {
$value = Devel::PartialDump->new->dump($value);
}
else {
$value = (defined $value ? overload::StrVal($value) : 'undef');
}
return "Validation failed for '" . $name . "' with value $value";
}
};
__PACKAGE__->meta->add_attribute('coercion' => (
accessor => 'coercion',
predicate => 'has_coercion',
Class::MOP::_definition_context(),
));
__PACKAGE__->meta->add_attribute('hand_optimized_type_constraint' => (
init_arg => 'optimized',
accessor => 'hand_optimized_type_constraint',
predicate => 'has_hand_optimized_type_constraint',
Class::MOP::_definition_context(),
));
__PACKAGE__->meta->add_attribute('inlined' => (
init_arg => 'inlined',
accessor => 'inlined',
predicate => '_has_inlined_type_constraint',
Class::MOP::_definition_context(),
));
__PACKAGE__->meta->add_attribute('inline_environment' => (
init_arg => 'inline_environment',
accessor => '_inline_environment',
default => sub { {} },
Class::MOP::_definition_context(),
));
sub parents {
my $self = shift;
$self->parent;
}
# private accessors
__PACKAGE__->meta->add_attribute('compiled_type_constraint' => (
accessor => '_compiled_type_constraint',
predicate => '_has_compiled_type_constraint',
Class::MOP::_definition_context(),
));
__PACKAGE__->meta->add_attribute('package_defined_in' => (
accessor => '_package_defined_in',
Class::MOP::_definition_context(),
));
sub new {
my $class = shift;
my ($first, @rest) = @_;
my %args = ref $first ? %$first : $first ? ($first, @rest) : ();
$args{name} = $args{name} ? "$args{name}" : "__ANON__";
if ( $args{optimized} ) {
Moose::Deprecated::deprecated(
feature => 'optimized type constraint sub ref',
message =>
'Providing an optimized subroutine ref for type constraints is deprecated.'
. ' Use the inlining feature (inline_as) instead.'
);
}
if ( exists $args{message}
&& (!ref($args{message}) || ref($args{message}) ne 'CODE') ) {
confess("The 'message' parameter must be a coderef");
}
my $self = $class->_new(%args);
$self->compile_type_constraint()
unless $self->_has_compiled_type_constraint;
$self->_default_message($_default_message_generator->($self->name))
unless $self->has_message;
return $self;
}
sub coerce {
my $self = shift;
my $coercion = $self->coercion;
unless ($coercion) {
require Moose;
Moose->throw_error("Cannot coerce without a type coercion");
}
return $_[0] if $self->check($_[0]);
return $coercion->coerce(@_);
}
sub assert_coerce {
my $self = shift;
my $coercion = $self->coercion;
unless ($coercion) {
require Moose;
Moose->throw_error("Cannot coerce without a type coercion");
}
return $_[0] if $self->check($_[0]);
my $result = $coercion->coerce(@_);
$self->assert_valid($result);
return $result;
}
sub check {
my ($self, @args) = @_;
my $constraint_subref = $self->_compiled_type_constraint;
return $constraint_subref->(@args) ? 1 : undef;
}
sub validate {
my ($self, $value) = @_;
if ($self->_compiled_type_constraint->($value)) {
return undef;
}
else {
$self->get_message($value);
}
}
sub can_be_inlined {
my $self = shift;
if ( $self->has_parent && $self->constraint == $null_constraint ) {
return $self->parent->can_be_inlined;
}
return $self->_has_inlined_type_constraint;
}
sub _inline_check {
my $self = shift;
unless ( $self->can_be_inlined ) {
require Moose;
Moose->throw_error( 'Cannot inline a type constraint check for ' . $self->name );
}
if ( $self->has_parent && $self->constraint == $null_constraint ) {
return $self->parent->_inline_check(@_);
}
return '( do { ' . $self->inlined->( $self, @_ ) . ' } )';
}
sub inline_environment {
my $self = shift;
if ( $self->has_parent && $self->constraint == $null_constraint ) {
return $self->parent->inline_environment;
}
return $self->_inline_environment;
}
sub assert_valid {
my ($self, $value) = @_;
my $error = $self->validate($value);
return 1 if ! defined $error;
require Moose;
Moose->throw_error($error);
}
sub get_message {
my ($self, $value) = @_;
my $msg = $self->has_message
? $self->message
: $self->_default_message;
local $_ = $value;
return $msg->($value);
}
## type predicates ...
sub equals {
my ( $self, $type_or_name ) = @_;
my $other = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return;
return 1 if $self == $other;
if ( $self->has_hand_optimized_type_constraint and $other->has_hand_optimized_type_constraint ) {
return 1 if $self->hand_optimized_type_constraint == $other->hand_optimized_type_constraint;
}
return unless $self->constraint == $other->constraint;
if ( $self->has_parent ) {
return unless $other->has_parent;
return unless $self->parent->equals( $other->parent );
} else {
return if $other->has_parent;
}
return;
}
sub is_a_type_of {
my ($self, $type_or_name) = @_;
my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return;
($self->equals($type) || $self->is_subtype_of($type));
}
sub is_subtype_of {
my ($self, $type_or_name) = @_;
my $type = Moose::Util::TypeConstraints::find_type_constraint($type_or_name) or return;
my $current = $self;
while (my $parent = $current->parent) {
return 1 if $parent->equals($type);
$current = $parent;
}
return 0;
}
## compiling the type constraint
sub compile_type_constraint {
my $self = shift;
$self->_compiled_type_constraint($self->_actually_compile_type_constraint);
}
## type compilers ...
sub _actually_compile_type_constraint {
my $self = shift;
return $self->_compile_hand_optimized_type_constraint
if $self->has_hand_optimized_type_constraint;
if ( $self->can_be_inlined ) {
return eval_closure(
source => 'sub { ' . $self->_inline_check('$_[0]') . ' }',
environment => $self->inline_environment,
);
}
my $check = $self->constraint;
unless ( defined $check ) {
require Moose;
Moose->throw_error( "Could not compile type constraint '"
. $self->name
. "' because no constraint check" );
}
return $self->_compile_subtype($check)
if $self->has_parent;
return $self->_compile_type($check);
}
sub _compile_hand_optimized_type_constraint {
my $self = shift;
my $type_constraint = $self->hand_optimized_type_constraint;
unless ( ref $type_constraint ) {
require Moose;
Moose->throw_error("Hand optimized type constraint is not a code reference");
}
return $type_constraint;
}
sub _compile_subtype {
my ($self, $check) = @_;
# gather all the parent constraintss in order
my @parents;
my $optimized_parent;
foreach my $parent ($self->_collect_all_parents) {
# if a parent is optimized, the optimized constraint already includes
# all of its parents tcs, so we can break the loop
if ($parent->has_hand_optimized_type_constraint) {
push @parents => $optimized_parent = $parent->hand_optimized_type_constraint;
last;
}
else {
push @parents => $parent->constraint;
}
}
@parents = grep { $_ != $null_constraint } reverse @parents;
unless ( @parents ) {
return $self->_compile_type($check);
} elsif( $optimized_parent and @parents == 1 ) {
# the case of just one optimized parent is optimized to prevent
# looping and the unnecessary localization
if ( $check == $null_constraint ) {
return $optimized_parent;
} else {
return subname($self->name, sub {
return undef unless $optimized_parent->($_[0]);
my (@args) = @_;
local $_ = $args[0];
$check->(@args);
});
}
} else {
# general case, check all the constraints, from the first parent to ourselves
my @checks = @parents;
push @checks, $check if $check != $null_constraint;
return subname($self->name => sub {
my (@args) = @_;
local $_ = $args[0];
foreach my $check (@checks) {
return undef unless $check->(@args);
}
return 1;
});
}
}
sub _compile_type {
my ($self, $check) = @_;
return $check if $check == $null_constraint; # Item, Any
return subname($self->name => sub {
my (@args) = @_;
local $_ = $args[0];
$check->(@args);
});
}
## other utils ...
sub _collect_all_parents {
my $self = shift;
my @parents;
my $current = $self->parent;
while (defined $current) {
push @parents => $current;
$current = $current->parent;
}
return @parents;
}
sub create_child_type {
my ($self, %opts) = @_;
my $class = ref $self;
return $class->new(%opts, parent => $self);
}
1;
# ABSTRACT: The Moose Type Constraint metaclass
=pod
=head1 NAME
Moose::Meta::TypeConstraint - The Moose Type Constraint metaclass
=head1 VERSION
version 2.0604
=head1 DESCRIPTION
This class represents a single type constraint. Moose's built-in type
constraints, as well as constraints you define, are all stored in a
L<Moose::Meta::TypeConstraint::Registry> object as objects of this
class.
=head1 INHERITANCE
C<Moose::Meta::TypeConstraint> is a subclass of L<Class::MOP::Object>.
=head1 METHODS
=over 4
=item B<< Moose::Meta::TypeConstraint->new(%options) >>
This creates a new type constraint based on the provided C<%options>:
=over 8
=item * name
The constraint name. If a name is not provided, it will be set to
"__ANON__".
=item * parent
A C<Moose::Meta::TypeConstraint> object which is the parent type for
the type being created. This is optional.
=item * constraint
This is the subroutine reference that implements the actual constraint
check. This defaults to a subroutine which always returns true.
=item * message
A subroutine reference which is used to generate an error message when
the constraint fails. This is optional.
=item * coercion
A L<Moose::Meta::TypeCoercion> object representing the coercions to
the type. This is optional.
=item * inlined
A subroutine which returns a string suitable for inlining this type
constraint. It will be called as a method on the type constraint object, and
will receive a single additional parameter, a variable name to be tested
(usually C<"$_"> or C<"$_[0]">.
This is optional.
=item * inline_environment
A hash reference of variables to close over. The keys are variables names, and
the values are I<references> to the variables.
=item * optimized
B<This option is deprecated.>
This is a variant of the C<constraint> parameter that is somehow
optimized. Typically, this means incorporating both the type's
constraint and all of its parents' constraints into a single
subroutine reference.
=back
=item B<< $constraint->equals($type_name_or_object) >>
Returns true if the supplied name or type object is the same as the
current type.
=item B<< $constraint->is_subtype_of($type_name_or_object) >>
Returns true if the supplied name or type object is a parent of the
current type.
=item B<< $constraint->is_a_type_of($type_name_or_object) >>
Returns true if the given type is the same as the current type, or is
a parent of the current type. This is a shortcut for checking
C<equals> and C<is_subtype_of>.
=item B<< $constraint->coerce($value) >>
This will attempt to coerce the value to the type. If the type does not
have any defined coercions this will throw an error.
If no coercion can produce a value matching C<$constraint>, the original
value is returned.
=item B<< $constraint->assert_coerce($value) >>
This method behaves just like C<coerce>, but if the result is not valid
according to C<$constraint>, an error is thrown.
=item B<< $constraint->check($value) >>
Returns true if the given value passes the constraint for the type.
=item B<< $constraint->validate($value) >>
This is similar to C<check>. However, if the type I<is valid> then the
method returns an explicit C<undef>. If the type is not valid, we call
C<< $self->get_message($value) >> internally to generate an error
message.
=item B<< $constraint->assert_valid($value) >>
Like C<check> and C<validate>, this method checks whether C<$value> is
valid under the constraint. If it is, it will return true. If it is not,
an exception will be thrown with the results of
C<< $self->get_message($value) >>.
=item B<< $constraint->name >>
Returns the type's name, as provided to the constructor.
=item B<< $constraint->parent >>
Returns the type's parent, as provided to the constructor, if any.
=item B<< $constraint->has_parent >>
Returns true if the type has a parent type.
=item B<< $constraint->parents >>
Returns all of the types parents as an list of type constraint objects.
=item B<< $constraint->constraint >>
Returns the type's constraint, as provided to the constructor.
=item B<< $constraint->get_message($value) >>
This generates a method for the given value. If the type does not have
an explicit message, we generate a default message.
=item B<< $constraint->has_message >>
Returns true if the type has a message.
=item B<< $constraint->message >>
Returns the type's message as a subroutine reference.
=item B<< $constraint->coercion >>
Returns the type's L<Moose::Meta::TypeCoercion> object, if one
exists.
=item B<< $constraint->has_coercion >>
Returns true if the type has a coercion.
=item B<< $constraint->can_be_inlined >>
Returns true if this type constraint can be inlined. A type constraint which
subtypes an inlinable constraint and does not add an additional constraint
"inherits" its parent type's inlining.
=item B<< $constraint->hand_optimized_type_constraint >>
B<This method is deprecated.>
Returns the type's hand optimized constraint, as provided to the
constructor via the C<optimized> option.
=item B<< $constraint->has_hand_optimized_type_constraint >>
B<This method is deprecated.>
Returns true if the type has an optimized constraint.
=item B<< $constraint->create_child_type(%options) >>
This returns a new type constraint of the same class using the
provided C<%options>. The C<parent> option will be the current type.
This method exists so that subclasses of this class can override this
behavior and change how child types are created.
=back
=head1 BUGS
See L<Moose/BUGS> for details on reporting bugs.
=head1 AUTHOR
Moose is maintained by the Moose Cabal, along with the help of many contributors. See L<Moose/CABAL> and L<Moose/CONTRIBUTORS> for details.
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2012 by Infinity Interactive, Inc..
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut
__END__