Class: Dhall::Optional

Inherits:
Expression show all
Defined in:
lib/dhall/ast.rb,
lib/dhall/binary.rb,
lib/dhall/normalize.rb

Direct Known Subclasses

OptionalNone

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Expression

#&, #*, #+, #annotate, #as_dhall, #cache_key, #call, #concat, #deep_merge, #deep_merge_type, #dhall_eq, #digest, #fetch, #fusion, #merge, #resolve, #shift, #slice, #substitute, #to_binary, #to_cbor, #to_proc, #|

Constructor Details

#initialize(normalized: false, **attrs) ⇒ Optional

Returns a new instance of Optional.



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# File 'lib/dhall/ast.rb', line 584

def initialize(normalized: false, **attrs)
	@normalized = normalized
	super(**attrs)
end

Class Method Details

.as_dhall ⇒ Object 



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# File 'lib/dhall/ast.rb', line 580

def self.as_dhall
	Builtins[:Natural]
end

.decode(type, value = nil) ⇒ Object 



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# File 'lib/dhall/binary.rb', line 104

def self.decode(type, value=nil)
	if value.nil?
		OptionalNone.new(value_type: Dhall.decode(type))
	else
		Optional.new(
			value:      Dhall.decode(value),
			value_type: type.nil? ? type : Dhall.decode(type)
		)
	end
end

.for(value, type: nil) ⇒ Object 



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# File 'lib/dhall/ast.rb', line 572

def self.for(value, type: nil)
	if value.nil?
		OptionalNone.new(value_type: type)
	else
		Optional.new(value: value, value_type: type)
	end
end

Instance Method Details

#as_json ⇒ Object 



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# File 'lib/dhall/ast.rb', line 610

def as_json
	[5, @normalized ? nil : value_type&.as_json, value.as_json]
end

#map(type: nil, &block) ⇒ Object 



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# File 'lib/dhall/ast.rb', line 598

def map(type: nil, &block)
	with(value: block[value], value_type: type)
end

#normalize ⇒ Object 



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# File 'lib/dhall/normalize.rb', line 269

def normalize
	with(
		value:      value.normalize,
		value_type: value_type&.normalize,
		normalized: true
	)
end

#reduce(_, &block) ⇒ Object 



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# File 'lib/dhall/ast.rb', line 602

def reduce(_, &block)
	block[value]
end

#to_s ⇒ Object 



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# File 'lib/dhall/ast.rb', line 606

def to_s
	value.to_s
end

#type ⇒ Object 



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# File 'lib/dhall/ast.rb', line 589

def type
	return unless value_type

	Dhall::Application.new(
		function: Builtins[:Optional],
		argument: value_type
	)
end