/ 
Venus-3.02
River stage two • 3 direct dependents • 56 total dependents
/ Venus::Role::Assertable

NAME

Venus::Role::Assertable - Assertable Role

ABSTRACT

Assertable Role for Perl 5

SYNOPSIS

package Example;

use Venus::Class;
use Venus::Assert;

with 'Venus::Role::Assertable';

sub assertion {
  Venus::Assert->new('Example')->constraint('object', sub{
    $_->value->isa('Example')
  })
}

package main;

my $example = Example->new;

# $example->check;

DESCRIPTION

This package modifies the consuming package and requires methods for making the object assertable.

METHODS

This package provides the following methods:

assert

assert(Any $data) (Any)

The assert method returns the data provided if it passes the registered type constraints, or throws an exception.

Since 1.23

assert example 1
# given: synopsis

package main;

my $assert = $example->assert;

# Exception! (isa Venus::Assert::Error)
assert example 2
# given: synopsis

package main;

my $assert = $example->assert({});

# Exception! (isa Venus::Assert::Error)
assert example 3
# given: synopsis

package main;

my $assert = $example->assert($example);

# bless({}, "Example")

assertion

assertion() (Assert)

The assertion method receives no arguments and should returns a Venus::Assert object.

Since 1.23

assertion example 1
package main;

my $example = Example->new;

my $assertion = $example->assertion;

# bless({name => "Example"}, "Venus::Assert")

check

check(Any $data) (Bool)

The check method returns true if the data provided passes the registered type constraints, or returns false.

Since 1.23

check example 1
# given: synopsis

package main;

my $check = $example->check;

# 0
check example 2
# given: synopsis

package main;

my $check = $example->check({});

# 0
check example 3
# given: synopsis

package main;

my $check = $example->check($example);

# 1

coerce

coerce(Any $data) (Any)

The coerce method returns a coerced value if the data provided matches any of the registered type coercions, or returns the data provided.

Since 1.23

coerce example 1
# given: synopsis

package main;

my $assertion = $example->assertion;

$assertion->coercion('string', sub{ucfirst(lc($_->value))});

my $coerce = $assertion->coerce;

# undef
coerce example 2
# given: synopsis

package main;

my $assertion = $example->assertion;

$assertion->coercion('string', sub{ucfirst(lc($_->value))});

my $coerce = $assertion->coerce({});

# {}
coerce example 3
# given: synopsis

package main;

my $assertion = $example->assertion;

$assertion->coercion('string', sub{ucfirst(lc($_->value))});

my $coerce = $assertion->coerce('hello');

# "Hello"

make

make(Any $data) (Object)

The make method returns an instance of the invocant, if the data provided passes the registered type constraints, allowing for any coercion, or throws an exception. If the data provided is itself an instance of the invocant it will be returned unaltered.

Since 1.23

make example 1
# given: synopsis

package main;

my $make = $example->make;

# Exception! (isa Venus::Assert::Error)
make example 2
# given: synopsis

package main;

my $make = $example->make($example);

# bless({}, "Example")
make example 3
# given: synopsis

package main;

my $make = $example->make({});

# Exception! (isa Venus::Assert::Error)

AUTHORS

Awncorp, awncorp@cpan.org

LICENSE

Copyright (C) 2000, Al Newkirk.

This program is free software, you can redistribute it and/or modify it under the terms of the Apache license version 2.0.