Venus::Role::Makeable - Makeable Role
Makeable Role for Perl 5
package Person; use Venus::Class 'attr', 'error', 'with'; with 'Venus::Role::Makeable'; attr 'name'; attr 'father'; attr 'mother'; attr 'siblings'; sub make { my ($self, $value) = @_; error if !ref $value; return $self->new($value); } sub makers { { father => 'Person', mother => 'Person', name => 'Venus/String', siblings => 'Person', } } sub make_name { my ($self, $code, @args) = @_; return $self->$code(@args); } sub make_siblings { my ($self, $code, $class, $value) = @_; return [map $self->$code($class, $_), @$value]; } package main; my $person = Person->make({ name => 'me', father => {name => 'father'}, mother => {name => 'mother'}, siblings => [{name => 'brother'}, {name => 'sister'}], }); # $person # bless({...}, 'Person') # $person->name # bless({...}, 'Venus::String') # $person->father # bless({...}, 'Person') # $person->mother # bless({...}, 'Person') # $person->siblings # [bless({...}, 'Person'), bless({...}, 'Person'), ...]
This package modifies the consuming package and provides methods for hooking into object construction and coercing arguments into objects and values using the "make" protocol, i.e. using the "make" method (which performs fatal type checking and coercions) instead of the typical "new" method.
"make"
"new"
This package provides the following methods:
make_args(HashRef $data, HashRef $spec) (HashRef)
The make_args method replaces values in the data provided with objects corresponding to the specification provided. The specification should contains key/value pairs where the keys map to class attributes (or input parameters) and the values are Venus::Space compatible package names.
Since 1.30
1.30
package main; my $person = Person->new; my $data = $person->make_args( { father => { name => 'father' } }, { father => 'Person', }, ); # { # father => bless({...}, 'Person'), # }
make_attr(Str $name, Any $value) (Any)
The make_attr method is a surrogate accessor and gets and/or sets an instance attribute based on the makers rules, returning the made value.
makers
# given: synopsis package main; $person = Person->new( name => 'me', ); my $make_name = $person->make_attr('name'); # bless({value => "me"}, "Venus::String")
# given: synopsis package main; $person = Person->new( name => 'me', ); my $make_name = $person->make_attr('name', 'myself'); # bless({value => "myself"}, "Venus::String")
make_into(Str $class, Any $value) (Object)
The make_into method attempts to build and return an object based on the class name and value provided, unless the value provided is already an object derived from the specified class.
package main; my $person = Person->new; my $friend = $person->make_into('Person', { name => 'friend', }); # bless({...}, 'Person')
make_onto(HashRef $data, Str $name, Str $class, Any $value) (Object)
The make_onto method attempts to build and assign an object based on the class name and value provided, as the value corresponding to the name specified, in the data provided. If the $value is omitted, the value corresponding to the name in the $data will be used.
$value
$data
package main; my $person = Person->new; my $data = { friend => { name => 'friend' } }; my $friend = $person->make_onto($data, 'friend', 'Person'); # bless({...}, 'Person'), # $data was updated # # { # friend => bless({...}, 'Person'), # }
package Player; use Venus::Class; with 'Venus::Role::Makeable'; attr 'name'; attr 'teammates'; sub makers { { teammates => 'Person', } } sub make_into_person { my ($self, $class, $value) = @_; return $class->make($value); } sub make_into_venus_string { my ($self, $class, $value) = @_; return $class->make($value); } sub make_teammates { my ($self, $code, $class, $value) = @_; return [map $self->$code($class, $_), @$value]; } package main; my $player = Player->new; my $data = { teammates => [{ name => 'player2' }, { name => 'player3' }] }; my $teammates = $player->make_onto($data, 'teammates', 'Person'); # [bless({...}, 'Person'), bless({...}, 'Person')] # $data was updated # # { # teammates => [bless({...}, 'Person'), bless({...}, 'Person')], # }
makers() (HashRef)
The makers method, if defined, is called during object construction, or by the "making" method, and returns key/value pairs where the keys map to class attributes (or input parameters) and the values are Venus::Space compatible package names.
package main; my $person = Person->new( name => 'me', ); my $makers = $person->makers; # { # father => "Person", # mother => "Person", # name => "Venus/String", # siblings => "Person", # }
making(HashRef $data) (HashRef)
The making method is called automatically during object construction but can be called manually as well, and is passed a hashref to make and return.
package main; my $person = Person->new; my $making = $person->making({ name => 'me', }); # $making # {...} # $making->{name} # bless({...}, 'Venus::String') # $making->{father} # undef # $making->{mother} # undef # $making->{siblings} # undef
package main; my $person = Person->new; my $making = $person->making({ name => 'me', mother => {name => 'mother'}, siblings => [{name => 'brother'}, {name => 'sister'}], }); # $making # {...} # $making->{name} # bless({...}, 'Venus::String') # $making->{father} # undef # $making->{mother} # bless({...}, 'Person') # $making->{siblings} # [bless({...}, 'Person'), bless({...}, 'Person'), ...]
To install Venus, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Venus
CPAN shell
perl -MCPAN -e shell install Venus
For more information on module installation, please visit the detailed CPAN module installation guide.