package Specio::Constraint::Role::Interface;
use strict;
use warnings;
our $VERSION = '0.12';
use Carp qw( confess );
use Class::Method::Modifiers ();
use Devel::PartialDump;
use List::Util 1.33 qw( all any );
use Specio::Exception;
use Specio::TypeChecks qw( is_CodeRef );
use Sub::Quote qw( quote_sub );
use Try::Tiny;
use Role::Tiny;
use Specio::Role::Inlinable;
with 'Specio::Role::Inlinable';
use overload(
q{""} => sub { $_[0] },
'&{}' => '_subify',
'bool' => sub {1},
);
{
## no critic (Subroutines::ProtectPrivateSubs)
my $role_attrs = Specio::Role::Inlinable::_attrs();
## use critic
my $attrs = {
%{$role_attrs},
name => {
is => 'bare',
isa => 'Str',
predicate => '_has_name',
},
parent => {
is => 'bare',
does => 'Specio::Constraint::Role::Interface',
predicate => '_has_parent',
},
_constraint => {
is => 'bare',
isa => 'CodeRef',
init_arg => 'constraint',
predicate => '_has_constraint',
},
_optimized_constraint => {
is => 'bare',
isa => 'CodeRef',
init_arg => undef,
lazy => 1,
builder => '_build_optimized_constraint',
},
_ancestors => {
is => 'bare',
isa => 'ArrayRef',
init_arg => undef,
lazy => 1,
builder => '_build_ancestors',
},
_message_generator => {
is => 'bare',
isa => 'CodeRef',
init_arg => undef,
},
_coercions => {
is => 'bare',
builder => '_build_coercions',
},
# Because types are cloned on import, we can't directly compare type
# objects. Because type names can be reused between packages (no global
# registry) we can't compare types based on name either.
_signature => {
is => 'bare',
isa => 'Str',
init_arg => undef,
lazy => 1,
builder => '_build_signature',
},
};
## no critic (Subroutines::ProhibitUnusedPrivateSubroutines)
sub _attrs {
return $attrs;
}
}
my $NullConstraint = sub {1};
sub BUILD { }
around BUILD => sub {
my $orig = shift;
my $self = shift;
my $p = shift;
unless ( $self->_has_constraint() || $self->_has_inline_generator() ) {
$self->_set_constraint($NullConstraint);
}
die
'A type constraint should have either a constraint or inline_generator parameter, not both'
if $self->_has_constraint() && $self->_has_inline_generator();
$self->{_message_generator}
= $self->_wrap_message_generator( $p->{message_generator} );
return;
};
sub _set_constraint {
is_CodeRef( $_[1] )
or confess '_set_constraint() must be given a coderef, not a '
. Devel::PartialDump->new()->dump( $_[1] );
$_[0]->{_constraint} = $_[1];
}
sub _wrap_message_generator {
my $self = shift;
my $generator = shift;
$generator //= sub {
my $description = shift;
my $value = shift;
return "Validation failed for $description with value "
. Devel::PartialDump->new()->dump($value);
};
my $d = $self->_description();
return sub { $generator->( $d, @_ ) };
}
sub coercions { values %{ $_[0]->{coercions} } }
sub coercion_from_type { $_[0]->{coercions}{ $_[1] } }
sub _has_coercion_from_type { exists $_[0]->{coercions}{ $_[1] } }
sub _add_coercion { $_[0]->{coercions}{ $_[1] } = $_[2] }
sub has_coercions { scalar keys %{ $_[0]->{coercions} } }
sub validate_or_die {
my $self = shift;
my $value = shift;
return if $self->value_is_valid($value);
Specio::Exception->throw(
message => $self->_message_generator()->($value),
type => $self,
value => $value,
);
}
sub value_is_valid {
my $self = shift;
my $value = shift;
return $self->_optimized_constraint()->($value);
}
sub _ancestors_and_self {
my $self = shift;
return ( ( reverse @{ $self->_ancestors() } ), $self );
}
sub is_a_type_of {
my $self = shift;
my $type = shift;
return any { $_->_signature() eq $type->_signature() }
$self->_ancestors_and_self();
}
sub is_same_type_as {
my $self = shift;
my $type = shift;
return $self->_signature() eq $type->_signature();
}
sub is_anon {
my $self = shift;
return !$self->_has_name();
}
sub has_real_constraint {
my $self = shift;
return ( $self->_has_constraint
&& $self->_constraint() ne $NullConstraint )
|| $self->_has_inline_generator();
}
sub inline_check {
my $self = shift;
die 'Cannot inline' unless $self->_has_inline_generator();
return $self->_inline_generator()->( $self, @_ );
}
sub _build_optimized_constraint {
my $self = shift;
if ( $self->can_be_inlined() ) {
return $self->_generated_inline_sub();
}
else {
return $self->_constraint_with_parents();
}
}
sub _constraint_with_parents {
my $self = shift;
my @constraints;
for my $type ( $self->_ancestors_and_self() ) {
next unless $type->has_real_constraint();
# If a type can be inlined, we can use that and discard all of the
# ancestors we've seen so far, since we can assume that the inlined
# constraint does all of the ancestor checks in addition to its own.
if ( $type->can_be_inlined() ) {
@constraints = $type->_generated_inline_sub();
}
else {
push @constraints, $type->_constraint();
}
}
return $NullConstraint unless @constraints;
return sub {
all { $_->( $_[0] ) } @constraints;
};
}
# This is only used for identifying from types as part of coercions, but I
# want to leave open the possibility of using something other than
# _description in the future.
sub id {
my $self = shift;
return $self->_description();
}
sub add_coercion {
my $self = shift;
my $coercion = shift;
my $from_id = $coercion->from()->id();
confess "Cannot add two coercions fom the same type: $from_id"
if $self->_has_coercion_from_type($from_id);
$self->_add_coercion( $from_id => $coercion );
return;
}
sub has_coercion_from_type {
my $self = shift;
my $type = shift;
return $self->_has_coercion_from_type( $type->id() );
}
sub coerce_value {
my $self = shift;
my $value = shift;
for my $coercion ( $self->coercions() ) {
next unless $coercion->from()->value_is_valid($value);
return $coercion->coerce($value);
}
return $value;
}
sub can_inline_coercion_and_check {
my $self = shift;
return all { $_->can_be_inlined() } $self, $self->coercions();
}
{
my $counter = 1;
sub inline_coercion_and_check {
my $self = shift;
die 'Cannot inline coercion and check'
unless $self->can_inline_coercion_and_check();
my $type_var_name = '$_Specio_Constraint_Interface_type' . $counter;
my $message_generator_var_name
= '$_Specio_Constraint_Interface_message_generator' . $counter;
my %env = (
$type_var_name => \$self,
$message_generator_var_name => \( $self->_message_generator() ),
%{ $self->_inline_environment() },
);
my $source = 'do {' . 'my $value = ' . $_[0] . ';';
for my $coercion ( $self->coercions() ) {
$source
.= '$value = '
. $coercion->inline_coercion( $_[0] ) . ' if '
. $coercion->from()->inline_check( $_[0] ) . ';';
%env = ( %env, %{ $coercion->_inline_environment() } );
}
$source .= $self->inline_check('$value');
$source .= ' or ';
$source .= $self->_inline_throw_exception(
'$value',
$message_generator_var_name,
$type_var_name
);
$source .= ';';
$source .= '$value };';
$counter++;
return ( $source, \%env );
}
}
sub _subify {
my $self = shift;
if ( $self->can_be_inlined() ) {
my $inline = $self->inline_check('$_[0]');
$inline .= ' or ';
my %env = (
'$message_generator' => \( $self->_message_generator() ),
'$type' => \$self,
);
$inline .= $self->_inline_throw_exception(
'$_[0]',
'$message_generator',
'$type',
);
return quote_sub( $inline, \%env );
}
else {
return sub { $self->validate_or_die( $_[0] ) };
}
}
sub _inline_throw_exception {
my $self = shift;
my $value_var = shift;
my $message_generator_var_name = shift;
my $type_var_name = shift;
#<<<
return 'Specio::Exception->throw( '
. ' message => ' . $message_generator_var_name . '->(' . $value_var . '),'
. ' type => ' . $type_var_name . ','
. ' value => ' . $value_var . ' )';
#>>>
}
# This exists for the benefit of Moo
sub coercion_sub {
my $self = shift;
if ( all { $_->can_be_inlined() } $self->coercions() ) {
my $inline = q{};
my %env;
for my $coercion ( $self->coercions() ) {
$inline
.= '$_[0] = '
. $coercion->inline_coercion('$_[0]') . ' if '
. $coercion->from()->inline_check(' $_[0]') . ';';
%env = ( %env, %{ $coercion->_inline_environment() } );
}
return quote_sub( $inline, \%env );
}
else {
return sub { $self->coerce_value(shift) };
}
}
sub _build_ancestors {
my $self = shift;
my @parents;
my $type = $self;
while ( $type = $type->parent() ) {
push @parents, $type;
}
return \@parents;
}
sub _build_description {
my $self = shift;
my $desc
= $self->is_anon() ? 'anonymous type' : 'type named ' . $self->name();
$desc .= q{ } . $self->declared_at()->description();
return $desc;
}
sub _build_coercions { {} }
sub _build_signature {
my $self = shift;
# This assumes that when a type is cloned, the underlying constraint or
# generator sub is copied by _reference_, so it has the same memory
# address and stringifies to the same value. XXX - will this break under
# threads?
return join "\n",
( $self->_has_parent() ? $self->parent()->_signature() : () ),
( $self->_constraint() // $self->_inline_generator() );
}
# Moose compatibility methods - these exist as a temporary hack to make Specio
# work with Moose.
sub has_coercion {
shift->has_coercions();
}
## no critic (Subroutines::ProhibitUnusedPrivateSubroutines)
sub _inline_check {
shift->inline_check(@_);
}
sub _compiled_type_constraint {
shift->_optimized_constraint();
}
## use critic;
# This class implements the methods that Moose expects from coercions as well.
sub coercion {
return shift;
}
## no critic (Subroutines::ProhibitUnusedPrivateSubroutines)
sub _compiled_type_coercion {
my $self = shift;
return sub {
return $self->coerce_value(shift);
};
}
## use critic
sub inline_environment {
shift->_inline_environment();
}
sub has_message {
1;
}
sub message {
shift->_message_generator();
}
sub get_message {
my $self = shift;
my $value = shift;
return $self->_message_generator()->( $self, $value );
}
sub check {
shift->value_is_valid(@_);
}
sub coerce {
shift->coerce_value(@_);
}
1;
# ABSTRACT: The interface all type constraints should provide
__END__
=pod
=head1 NAME
Specio::Constraint::Role::Interface - The interface all type constraints should provide
=head1 VERSION
version 0.12
=head1 DESCRIPTION
This role defines the interface that all type constraints must provide, and
provides most (or all) of the implementation. The L<Specio::Constraint::Simple>
class simply consumes this role and provides no additional code. Other
constraint classes add features or override some of this role's functionality.
=for Pod::Coverage .*
=head1 API
See the L<Specio::Constraint::Simple> documentation for details. See the
internals of various constraint classes to see how this role can be overridden
or expanded upon.
=head1 ROLES
This role does the L<Specio::Role::Inlinable> role.
=head1 AUTHOR
Dave Rolsky <autarch@urth.org>
=head1 COPYRIGHT AND LICENSE
This software is Copyright (c) 2015 by Dave Rolsky.
This is free software, licensed under:
The Artistic License 2.0 (GPL Compatible)
=cut