63 lines
1.3 KiB
Ruby
63 lines
1.3 KiB
Ruby
module Morpher
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class Compiler
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# Compiler with evaluators as output
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class Evaluator < self
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include Concord.new(:evaluators, :emitters)
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# Return evaluator tree for node
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#
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# @param [Node] node
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#
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# @return [Evalautor]
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# on success
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#
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# @raise [Compiler::Error]
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# on error
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#
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# @api private
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#
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def call(node)
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evaluator = evaluator(node)
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emitter = emitter(evaluator)
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emitter.call(self, evaluator, node)
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end
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private
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# Lookup evaluator for node
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#
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# @param [Node]
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#
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# @return [Class:Evaluator]
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# if found
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#
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# @raise [Error::UnknownNode]
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# otherwise
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#
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# @api private
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#
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def evaluator(node)
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type = node.type
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evaluators.fetch(type) do
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fail Error::UnknownNode, type
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end
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end
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# Return emitter for evaluator
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#
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# @param [Class:Evalautor]
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#
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# @return [#call]
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#
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# @api private
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#
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def emitter(evaluator)
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emitters.each do |arity, emitter|
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return emitter if evaluator.ancestors.include?(arity)
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end
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fail Error::UnknownNode, evaluator
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end
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end # Evaluator
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end # Compiler
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end # Morpher
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