`class Type`

Converts input values to a specific application type.

Definitions

`def self.expected(type)`

Resolve the expected output type of a converter.

Implementation

def self.expected(type)
	if type.respond_to?(:type)
		return type.type
	else
		return type
	end
end

`def initialize(type, &converter)`

Initialize a type converter.

Signature

parameter　type　Object: The expected converted type.
yields　{|value| ...}: The conversion operation.

Implementation

def initialize(type, &converter)
	@type = type
	@converter = converter
end

`attr :type`

The expected converted type.

`def call(value)`

Convert a value to the declared type.

Signature

parameter　value　Object: The input value.
returns　Object: The converted value.
raises　TypeError: If the value cannot be converted.

Implementation

def call(value)
	# Preserve values which already have the expected type:
	if @type === value
		return value
	end
	
	if @converter
		value = @converter.call(value)
		
		# Ensure converters produce the type they declare:
		if @type === value
			return value
		end
	end
	
	raise TypeError, "Could not convert #{value.inspect} to #{@type}!"
end