60 lines
1.3 KiB
Ruby
60 lines
1.3 KiB
Ruby
# frozen_string_literal: true
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module Mutant
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# Abstract base class for match expression
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class Expression
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include AbstractType, Adamantium::Flat
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fragment = /[A-Za-z][A-Za-z\d_]*/.freeze
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SCOPE_NAME_PATTERN = /(?<scope_name>#{fragment}(?:#{SCOPE_OPERATOR}#{fragment})*)/.freeze
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SCOPE_SYMBOL_PATTERN = '(?<scope_symbol>[.#])'
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private_constant(*constants(false))
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# Syntax of expression
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#
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# @return [String]
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abstract_method :syntax
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# Match length with other expression
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#
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# @param [Expression] other
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#
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# @return [Integer]
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def match_length(other)
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if eql?(other)
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syntax.length
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else
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0
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end
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end
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# Test if expression is prefix
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#
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# @param [Expression] other
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#
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# @return [Boolean]
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def prefix?(other)
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!match_length(other).zero?
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end
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# Try to parse input into expression of receiver class
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#
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# @param [String] input
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#
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# @return [Expression]
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# when successful
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#
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# @return [nil]
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# otherwise
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def self.try_parse(input)
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match = self::REGEXP.match(input)
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return unless match
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names = anima.attribute_names
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new(Hash[names.zip(names.map(&match.method(:[])))])
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end
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end # Expression
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end # Mutant
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