Specio::Constraint::Structurable

Section: User Contributed Perl Documentation (3)
Updated: 2020-07-28
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NAME

Specio::Constraint::Structurable - A class which represents structurable constraints  

VERSION

version 0.46  

SYNOPSIS

    my $tuple = t('Tuple');

    my $tuple_of_str_int = $tuple->parameterize( of => [ t('Str'), t('Int') ] );

 

DESCRIPTION

This class implements the API for structurable types like "Dict", "Map"< and "Tuple".  

API

This class implements the same API as Specio::Constraint::Simple, with a few additions.  

Specio::Constraint::Structurable->new(...)

This class's constructor accepts two additional parameters:
parameterization_args_builder

This is a subroutine that takes the values passed to "of" and returns a hash of named arguments. These arguments will then be passed into the "structured_constraint_generator" or "structured_inline_generator".

This should also do argument checking to make sure that the argument passed are valid. For example, the "Tuple" type turns the arrayref passed to "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.

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 "Specio::Constraint::Structurable" object. It will be passed the hash of arguments returned by the "parameterization_args_builder".

This parameter is required.

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 "parameterization_args_builder".

This parameter is mutually exclusive with the "structured_inline_generator" parameter.

This parameter or the "structured_inline_generator" parameter is required.

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 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 "parameterization_args_builder".

This probably seems fairly confusing, so looking at the examples in the Specio::Library::Structured::* code may be helpful.

This parameter is mutually exclusive with the "structured_constraint_generator" parameter.

This parameter or the "structured_constraint_generator" parameter is required.

 

$type->parameterize(...)

This method takes two arguments. The "of" argument should be an object which does the Specio::Constraint::Role::Interface role, and is required.

The other argument, "declared_at", is optional. If it is not given, then a new Specio::DeclaredAt object is creating using a call stack depth of 1.

This method returns a new Specio::Constraint::Structured object.  

SUPPORT

Bugs may be submitted at <https://github.com/houseabsolute/Specio/issues>.

I am also usually active on IRC as 'autarch' on "irc://irc.perl.org".  

SOURCE

The source code repository for Specio can be found at <https://github.com/houseabsolute/Specio>.  

AUTHOR

Dave Rolsky <autarch@urth.org>  

COPYRIGHT AND LICENSE

This software is Copyright (c) 2012 - 2020 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 LICENSE file included with this distribution.


 

Index

NAME
VERSION
SYNOPSIS
DESCRIPTION
API
Specio::Constraint::Structurable->new(...)
$type->parameterize(...)
SUPPORT
SOURCE
AUTHOR
COPYRIGHT AND LICENSE