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module Morpher
class Evaluator
class Transformer
# Abstract namespace class for evaluators operating on hash keys
class Key < self
include AbstractType, Nullary::Parameterized, Intransitive
# Evaluator for dumping hash keys
class Dump < self
register :key_dump
# Call evaluator
#
# @param [Object] object
#
# @return [Array]
#
# @api private
#
def call(object)
[param, object]
end
# Return inverse evaluator
#
# @return [Fetch]
#
# @api private
#
def inverse
Fetch.new(param)
end
end # Dump
# Evaluator to fetch a specific hash key
class Fetch < self
register :key_fetch
# Call evaluator
#
# @param [Hash] object
#
# @return [Object]
#
# @api private
#
def call(object)
object.fetch(param) do
fail TransformError.new(self, object)
end
end
# Return evaluation
#
# @param [Object] input
#
# @return [Evaluation]
#
# @api private
#
def evaluation(input)
output = input.fetch(param) do
return evaluation_error(input)
end
evaluation_success(input, output)
end
# Return inverse evaluator
#
# @return [Dump]
#
# @api private
#
def inverse
Dump.new(param)
end
end # Fetch
end # Key
end # Transformer
end # Evaluator
end # Morpher
|
