X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FMouse%2FUtil%2FTypeConstraints.pm;h=808bb6b8def12625e695f0b5319f9656b8c6d28d;hb=9abaecfdec4e3ee1c8fae217b029a692155385a3;hp=e811ad5833efca840823c01a1e30ff46d5fce8c7;hpb=019047233180625898edb43732965d0dbda7e4b0;p=gitmo%2FMouse.git diff --git a/lib/Mouse/Util/TypeConstraints.pm b/lib/Mouse/Util/TypeConstraints.pm index e811ad5..808bb6b 100644 --- a/lib/Mouse/Util/TypeConstraints.pm +++ b/lib/Mouse/Util/TypeConstraints.pm @@ -1,200 +1,636 @@ package Mouse::Util::TypeConstraints; -use strict; -use warnings; -use base 'Exporter'; +use Mouse::Util; # enables strict and warnings -use Carp (); -use Scalar::Util qw/blessed looks_like_number openhandle/; +use Mouse::Meta::TypeConstraint; +use Mouse::Exporter; -our @EXPORT = qw( - as where message from via type subtype coerce class_type role_type enum +use Carp (); +use Scalar::Util (); + +Mouse::Exporter->setup_import_methods( + as_is => [qw( + as where message optimize_as + from via + + type subtype class_type role_type duck_type + enum + coerce + + find_type_constraint + register_type_constraint + )], ); +our @CARP_NOT = qw(Mouse::Meta::Attribute); + my %TYPE; -my %TYPE_SOURCE; -my %COERCE; -my %COERCE_KEYS; -sub as ($) { - as => $_[0] +# The root type +$TYPE{Any} = Mouse::Meta::TypeConstraint->new( + name => 'Any', +); + +my @builtins = ( + # $name => $parent, $code, + + # the base type + Item => 'Any', undef, + + # the maybe[] type + Maybe => 'Item', undef, + + # value types + Undef => 'Item', \&Undef, + Defined => 'Item', \&Defined, + Bool => 'Item', \&Bool, + Value => 'Defined', \&Value, + Str => 'Value', \&Str, + Num => 'Str', \&Num, + Int => 'Num', \&Int, + + # ref types + Ref => 'Defined', \&Ref, + ScalarRef => 'Ref', \&ScalarRef, + ArrayRef => 'Ref', \&ArrayRef, + HashRef => 'Ref', \&HashRef, + CodeRef => 'Ref', \&CodeRef, + RegexpRef => 'Ref', \&RegexpRef, + GlobRef => 'Ref', \&GlobRef, + + # object types + FileHandle => 'GlobRef', \&FileHandle, + Object => 'Ref', \&Object, + + # special string types + ClassName => 'Str', \&ClassName, + RoleName => 'ClassName', \&RoleName, +); + +while (my ($name, $parent, $code) = splice @builtins, 0, 3) { + $TYPE{$name} = Mouse::Meta::TypeConstraint->new( + name => $name, + parent => $TYPE{$parent}, + optimized => $code, + ); } -sub where (&) { - where => $_[0] + +# parametarizable types +$TYPE{Maybe} {constraint_generator} = \&_parameterize_Maybe_for; +$TYPE{ArrayRef}{constraint_generator} = \&_parameterize_ArrayRef_for; +$TYPE{HashRef} {constraint_generator} = \&_parameterize_HashRef_for; + +# sugars +sub as ($) { (as => $_[0]) } ## no critic +sub where (&) { (where => $_[0]) } ## no critic +sub message (&) { (message => $_[0]) } ## no critic +sub optimize_as (&) { (optimize_as => $_[0]) } ## no critic + +sub from { @_ } +sub via (&) { $_[0] } ## no critic + +# type utilities + +sub optimized_constraints { # DEPRECATED + Carp::cluck('optimized_constraints() has been deprecated'); + return \%TYPE; +} + +undef @builtins; # free the allocated memory +@builtins = keys %TYPE; # reuse it +sub list_all_builtin_type_constraints { @builtins } +sub list_all_type_constraints { keys %TYPE } + +sub _define_type { + my $is_subtype = shift; + my $name; + my %args; + + if(@_ == 1 && ref $_[0] ){ # @_ : { name => $name, where => ... } + %args = %{$_[0]}; + } + elsif(@_ == 2 && ref $_[1]) { # @_ : $name => { where => ... } + $name = $_[0]; + %args = %{$_[1]}; + } + elsif(@_ % 2) { # @_ : $name => ( where => ... ) + ($name, %args) = @_; + } + else{ # @_ : (name => $name, where => ...) + %args = @_; + } + + if(!defined $name){ + $name = $args{name}; + } + + $args{name} = $name; + + my $parent = delete $args{as}; + if($is_subtype && !$parent){ + $parent = delete $args{name}; + $name = undef; + } + + if(defined $parent) { + $args{parent} = find_or_create_isa_type_constraint($parent); + } + + if(defined $name){ + # set 'package_defined_in' only if it is not a core package + my $this = $args{package_defined_in}; + if(!$this){ + $this = caller(1); + if($this !~ /\A Mouse \b/xms){ + $args{package_defined_in} = $this; + } + } + + if(defined $TYPE{$name}){ + my $that = $TYPE{$name}->{package_defined_in} || __PACKAGE__; + if($this ne $that) { + my $note = ''; + if($that eq __PACKAGE__) { + $note = sprintf " ('%s' is %s type constraint)", + $name, + scalar(grep { $name eq $_ } list_all_builtin_type_constraints()) + ? 'a builtin' + : 'an implicitly created'; + } + Carp::croak("The type constraint '$name' has already been created in $that" + . " and cannot be created again in $this" . $note); + } + } + } + + $args{constraint} = delete $args{where} if exists $args{where}; + $args{optimized} = delete $args{optimized_as} if exists $args{optimized_as}; + + my $constraint = Mouse::Meta::TypeConstraint->new(%args); + + if(defined $name){ + return $TYPE{$name} = $constraint; + } + else{ + return $constraint; + } } -sub message (&) { - message => $_[0] + +sub type { + return _define_type 0, @_; } -sub from { @_ } -sub via (&) { - $_[0] +sub subtype { + return _define_type 1, @_; } -my $optimized_constraints; -my $optimized_constraints_base; -{ - no warnings 'uninitialized'; - %TYPE = ( - Any => sub { 1 }, - Item => sub { 1 }, - Bool => sub { - !defined($_) || $_ eq "" || "$_" eq '1' || "$_" eq '0' +sub coerce { # coerce $type, from $from, via { ... }, ... + my $type_name = shift; + my $type = find_type_constraint($type_name) + or Carp::croak("Cannot find type '$type_name', perhaps you forgot to load it."); + + $type->_add_type_coercions(@_); + return; +} + +sub class_type { + my($name, $options) = @_; + my $class = $options->{class} || $name; + + # ClassType + return subtype $name => ( + as => 'Object', + optimized_as => Mouse::Util::generate_isa_predicate_for($class), + class => $class, + ); +} + +sub role_type { + my($name, $options) = @_; + my $role = $options->{role} || $name; + + # RoleType + return subtype $name => ( + as => 'Object', + optimized_as => sub { + return Scalar::Util::blessed($_[0]) + && Mouse::Util::does_role($_[0], $role); }, - Undef => sub { !defined($_) }, - Defined => sub { defined($_) }, - Value => sub { defined($_) && !ref($_) }, - Num => sub { !ref($_) && looks_like_number($_) }, - Int => sub { defined($_) && !ref($_) && /^-?[0-9]+$/ }, - Str => sub { defined($_) && !ref($_) }, - ClassName => sub { Mouse::is_class_loaded($_) }, - Ref => sub { ref($_) }, - - ScalarRef => sub { ref($_) eq 'SCALAR' }, - ArrayRef => sub { ref($_) eq 'ARRAY' }, - HashRef => sub { ref($_) eq 'HASH' }, - CodeRef => sub { ref($_) eq 'CODE' }, - RegexpRef => sub { ref($_) eq 'Regexp' }, - GlobRef => sub { ref($_) eq 'GLOB' }, - - FileHandle => sub { - ref($_) eq 'GLOB' && openhandle($_) - or - blessed($_) && $_->isa("IO::Handle") + role => $role, + ); +} + +sub duck_type { + my($name, @methods); + + if(ref($_[0]) ne 'ARRAY'){ + $name = shift; + } + + @methods = (@_ == 1 && ref($_[0]) eq 'ARRAY') ? @{$_[0]} : @_; + + # DuckType + return _define_type 1, $name => ( + as => 'Object', + optimized_as => Mouse::Util::generate_can_predicate_for(\@methods), + message => sub { + my($object) = @_; + my @missing = grep { !$object->can($_) } @methods; + return ref($object) + . ' is missing methods ' + . Mouse::Util::quoted_english_list(@missing); }, + methods => \@methods, + ); +} + +sub enum { + my($name, %valid); + + if(!(@_ == 1 && ref($_[0]) eq 'ARRAY')){ + $name = shift; + } + + %valid = map{ $_ => undef } + (@_ == 1 && ref($_[0]) eq 'ARRAY' ? @{$_[0]} : @_); - Object => sub { blessed($_) && blessed($_) ne 'Regexp' }, + # EnumType + return _define_type 1, $name => ( + as => 'Str', + optimized_as => sub{ + return defined($_[0]) && !ref($_[0]) && exists $valid{$_[0]}; + }, ); +} + +sub _find_or_create_regular_type{ + my($spec, $create) = @_; + + return $TYPE{$spec} if exists $TYPE{$spec}; + + my $meta = Mouse::Util::get_metaclass_by_name($spec); - sub optimized_constraints { \%TYPE } - my @TYPE_KEYS = keys %TYPE; - sub list_all_builtin_type_constraints { @TYPE_KEYS } + if(!defined $meta){ + return $create ? class_type($spec) : undef; + } - @TYPE_SOURCE{@TYPE_KEYS} = (__PACKAGE__) x @TYPE_KEYS; + if(Mouse::Util::is_a_metarole($meta)){ + return role_type($spec); + } + else{ + return class_type($spec); + } } -sub type { - my $pkg = caller(0); - my($name, %conf) = @_; - if ($TYPE{$name} && $TYPE_SOURCE{$name} ne $pkg) { - Carp::croak "The type constraint '$name' has already been created in $TYPE_SOURCE{$name} and cannot be created again in $pkg"; - }; - my $constraint = $conf{where} || do { $TYPE{delete $conf{as} || 'Any' } }; +sub _find_or_create_parameterized_type{ + my($base, $param) = @_; - $TYPE_SOURCE{$name} = $pkg; - $TYPE{$name} = $constraint; + my $name = sprintf '%s[%s]', $base->name, $param->name; + + $TYPE{$name} ||= $base->parameterize($param, $name); } -sub subtype { - my $pkg = caller(0); - my($name, %conf) = @_; - if ($TYPE{$name} && $TYPE_SOURCE{$name} ne $pkg) { - Carp::croak "The type constraint '$name' has already been created in $TYPE_SOURCE{$name} and cannot be created again in $pkg"; - }; - my $constraint = $conf{where} || do { $TYPE{delete $conf{as} || 'Any' } }; - my $as = $conf{as} || ''; +sub _find_or_create_union_type{ + return if grep{ not defined } @_; + my @types = sort map{ $_->{type_constraints} ? @{$_->{type_constraints}} : $_ } @_; - $TYPE_SOURCE{$name} = $pkg; + my $name = join '|', @types; - if ($as = $TYPE{$as}) { - $TYPE{$name} = sub { $as->($_) && $constraint->($_) }; - } else { - $TYPE{$name} = $constraint; - } + # UnionType + $TYPE{$name} ||= Mouse::Meta::TypeConstraint->new( + name => $name, + type_constraints => \@types, + ); } -sub coerce { - my($name, %conf) = @_; +# The type parser - Carp::croak "Cannot find type '$name', perhaps you forgot to load it." - unless $TYPE{$name}; +# param : '[' type ']' | NOTHING +sub _parse_param { + my($c) = @_; - unless ($COERCE{$name}) { - $COERCE{$name} = {}; - $COERCE_KEYS{$name} = []; + if($c->{spec} =~ s/^\[//){ + my $type = _parse_type($c, 1); + + if($c->{spec} =~ s/^\]//){ + return $type; + } + Carp::croak("Syntax error in type: missing right square bracket in '$c->{orig}'"); } - while (my($type, $code) = each %conf) { - Carp::croak "A coercion action already exists for '$type'" - if $COERCE{$name}->{$type}; - Carp::croak "Could not find the type constraint ($type) to coerce from" - unless $TYPE{$type}; + return undef; +} - push @{ $COERCE_KEYS{$name} }, $type; - $COERCE{$name}->{$type} = $code; +# name : [\w.:]+ +sub _parse_name { + my($c, $create) = @_; + + if($c->{spec} =~ s/\A ([\w.:]+) //xms){ + return _find_or_create_regular_type($1, $create); } + Carp::croak("Syntax error in type: expect type name near '$c->{spec}' in '$c->{orig}'"); } -sub class_type { - my $pkg = caller(0); - my($name, $conf) = @_; - my $class = $conf->{class}; - subtype( - $name => where => sub { $_->isa($class) } - ); -} +# single_type : name param +sub _parse_single_type { + my($c, $create) = @_; -sub role_type { - my($name, $conf) = @_; - my $role = $conf->{role}; - subtype( - $name => where => sub { - return unless defined $_ && ref($_) && $_->isa('Mouse::Object'); - $_->meta->does_role($role); + my $type = _parse_name($c, $create); + my $param = _parse_param($c); + + if(defined $type){ + if(defined $param){ + return _find_or_create_parameterized_type($type, $param); } - ); + else { + return $type; + } + } + elsif(defined $param){ + Carp::croak("Undefined type with parameter [$param] in '$c->{orig}'"); + } + else{ + return undef; + } } -sub typecast_constraints { - my($class, $pkg, $type_constraint, $types, $value) = @_; +# type : single_type ('|' single_type)* +sub _parse_type { + my($c, $create) = @_; - local $_; - for my $type (ref($types) eq 'ARRAY' ? @{ $types } : ( $types )) { - next unless $COERCE{$type}; - for my $coerce_type (@{ $COERCE_KEYS{$type}}) { - $_ = $value; - next unless $TYPE{$coerce_type}->(); - $_ = $value; - $_ = $COERCE{$type}->{$coerce_type}->(); - return $_ if $type_constraint->(); + my $type = _parse_single_type($c, $create); + if($c->{spec}){ # can be an union type + my @types; + while($c->{spec} =~ s/^\|//){ + push @types, _parse_single_type($c, $create); + } + if(@types){ + return _find_or_create_union_type($type, @types); } } - return $value; + return $type; } -my $serial_enum = 0; -sub enum { - # enum ['small', 'medium', 'large'] - if (ref($_[0]) eq 'ARRAY') { - my @elements = @{ shift @_ }; - my $name = 'Mouse::Util::TypeConstaints::Enum::Serial::' - . ++$serial_enum; - enum($name, @elements); - return $name; - } +sub find_type_constraint { + my($spec) = @_; + return $spec if Mouse::Util::is_a_type_constraint($spec) or not defined $spec; - # enum size => 'small', 'medium', 'large' - my $name = shift; - my %is_valid = map { $_ => 1 } @_; + $spec =~ s/\s+//g; + return $TYPE{$spec}; +} - subtype( - $name => where => sub { $is_valid{$_} } - ); +sub register_type_constraint { + my($constraint) = @_; + Carp::croak("No type supplied / type is not a valid type constraint") + unless Mouse::Util::is_a_type_constraint($constraint); + my $name = $constraint->name; + Carp::croak("Can't register an unnamed type constraint") + unless defined $name; + return $TYPE{$name} = $constraint; } -1; +sub find_or_parse_type_constraint { + my($spec) = @_; + return $spec if Mouse::Util::is_a_type_constraint($spec) or not defined $spec; + + $spec =~ s/\s+//g; + return $TYPE{$spec} || do{ + my $context = { + spec => $spec, + orig => $spec, + }; + my $type = _parse_type($context); + if($context->{spec}){ + Carp::croak("Syntax error: extra elements '$context->{spec}' in '$context->{orig}'"); + } + $type; + }; +} + +sub find_or_create_does_type_constraint{ + # XXX: Moose does not register a new role_type, but Mouse does. + return find_or_parse_type_constraint(@_) || role_type(@_); +} + +sub find_or_create_isa_type_constraint { + # XXX: Moose does not register a new class_type, but Mouse does. + return find_or_parse_type_constraint(@_) || class_type(@_); +} + +1; __END__ =head1 NAME -Mouse::Util::TypeConstraints - simple type constraints +Mouse::Util::TypeConstraints - Type constraint system for Mouse + +=head1 VERSION + +This document describes Mouse version 0.76 + +=head2 SYNOPSIS + + use Mouse::Util::TypeConstraints; + + subtype 'Natural' + => as 'Int' + => where { $_ > 0 }; + + subtype 'NaturalLessThanTen' + => as 'Natural' + => where { $_ < 10 } + => message { "This number ($_) is not less than ten!" }; + + coerce 'Num' + => from 'Str' + => via { 0+$_ }; + + enum 'RGBColors' => qw(red green blue); + + no Mouse::Util::TypeConstraints; + +=head1 DESCRIPTION + +This module provides Mouse with the ability to create custom type +constraints to be used in attribute definition. + +=head2 Important Caveat + +This is B a type system for Perl 5. These are type constraints, +and they are not used by Mouse unless you tell it to. No type +inference is performed, expressions are not typed, etc. etc. etc. + +A type constraint is at heart a small "check if a value is valid" +function. A constraint can be associated with an attribute. This +simplifies parameter validation, and makes your code clearer to read, +because you can refer to constraints by name. + +=head2 Slightly Less Important Caveat + +It is B a good idea to quote your type names. + +This prevents Perl from trying to execute the call as an indirect +object call. This can be an issue when you have a subtype with the +same name as a valid class. + +For instance: + + subtype DateTime => as Object => where { $_->isa('DateTime') }; + +will I, while this: + + use DateTime; + subtype DateTime => as Object => where { $_->isa('DateTime') }; + +will fail silently and cause many headaches. The simple way to solve +this, as well as future proof your subtypes from classes which have +yet to have been created, is to quote the type name: + + use DateTime; + subtype 'DateTime' => as 'Object' => where { $_->isa('DateTime') }; + +=head2 Default Type Constraints + +This module also provides a simple hierarchy for Perl 5 types, here is +that hierarchy represented visually. + + Any + Item + Bool + Maybe[`a] + Undef + Defined + Value + Str + Num + Int + ClassName + RoleName + Ref + ScalarRef + ArrayRef[`a] + HashRef[`a] + CodeRef + RegexpRef + GlobRef + FileHandle + Object + +B Any type followed by a type parameter C<[`a]> can be +parameterized, this means you can say: + + ArrayRef[Int] # an array of integers + HashRef[CodeRef] # a hash of str to CODE ref mappings + Maybe[Str] # value may be a string, may be undefined + +If Mouse finds a name in brackets that it does not recognize as an +existing type, it assumes that this is a class name, for example +C. + +B The C type constraint for the most part works +correctly now, but edge cases may still exist, please use it +sparingly. + +B The C type constraint does a complex package +existence check. This means that your class B be loaded for this +type constraint to pass. + +B The C constraint checks a string is a I which is a role, like C<'MyApp::Role::Comparable'>. The C +constraint checks that an I the named role. + +=head2 Type Constraint Naming + +Type name declared via this module can only contain alphanumeric +characters, colons (:), and periods (.). + +Since the types created by this module are global, it is suggested +that you namespace your types just as you would namespace your +modules. So instead of creating a I type for your +B module, you would call the type +I instead. + +=head2 Use with Other Constraint Modules + +This module can play nicely with other constraint modules with some +slight tweaking. The C clause in types is expected to be a +C reference which checks it's first argument and returns a +boolean. Since most constraint modules work in a similar way, it +should be simple to adapt them to work with Mouse. + +For instance, this is how you could use it with +L to declare a completely new type. + + type 'HashOfArrayOfObjects', + { + where => IsHashRef( + -keys => HasLength, + -values => IsArrayRef(IsObject) + ) + }; + +Here is an example of using L and it's non-test +related C function. + + type 'ArrayOfHashOfBarsAndRandomNumbers' + => where { + eq_deeply($_, + array_each(subhashof({ + bar => isa('Bar'), + random_number => ignore() + }))) + }; =head1 METHODS -=head2 optimized_constraints -> HashRef[CODE] +=head2 C<< list_all_builtin_type_constraints -> (Names) >> + +Returns the names of builtin type constraints. + +=head2 C<< list_all_type_constraints -> (Names) >> + +Returns the names of all the type constraints. + +=head1 FUNCTIONS + +=over 4 + +=item C<< type $name => where { } ... -> Mouse::Meta::TypeConstraint >> + +=item C<< subtype $name => as $parent => where { } ... -> Mouse::Meta::TypeConstraint >> + +=item C<< subtype as $parent => where { } ... -> Mouse::Meta::TypeConstraint >> + +=item C<< class_type ($class, ?$options) -> Mouse::Meta::TypeConstraint >> + +=item C<< role_type ($role, ?$options) -> Mouse::Meta::TypeConstraint >> + +=item C<< duck_type($name, @methods | \@methods) -> Mouse::Meta::TypeConstraint >> + +=item C<< duck_type(\@methods) -> Mouse::Meta::TypeConstraint >> + +=item C<< enum($name, @values | \@values) -> Mouse::Meta::TypeConstraint >> + +=item C<< enum (\@values) -> Mouse::Meta::TypeConstraint >> + +=item C<< coerce $type => from $another_type, via { }, ... >> + +=back + +=over 4 + +=item C<< find_type_constraint(Type) -> Mouse::Meta::TypeConstraint >> + +=back + +=head1 THANKS + +Much of this documentation was taken from C + +=head1 SEE ALSO -Returns the simple type constraints that Mouse understands. +L =cut