Class: Lrama::Grammar::Rule

Inherits:
Struct
  • Object
show all
Defined in:
lib/lrama/grammar/rule.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#code ⇒ Object

Returns the value of attribute code



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# File 'lib/lrama/grammar/rule.rb', line 3

def code
  @code
end

#id ⇒ Object

Returns the value of attribute id



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# File 'lib/lrama/grammar/rule.rb', line 3

def id
  @id
end

#lhs ⇒ Object

Returns the value of attribute lhs



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# File 'lib/lrama/grammar/rule.rb', line 3

def lhs
  @lhs
end

#lineno ⇒ Object

Returns the value of attribute lineno



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# File 'lib/lrama/grammar/rule.rb', line 3

def lineno
  @lineno
end

#nullable ⇒ Object

Returns the value of attribute nullable



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# File 'lib/lrama/grammar/rule.rb', line 3

def nullable
  @nullable
end

#precedence_sym ⇒ Object

Returns the value of attribute precedence_sym



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# File 'lib/lrama/grammar/rule.rb', line 3

def precedence_sym
  @precedence_sym
end

#rhs ⇒ Object

Returns the value of attribute rhs



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# File 'lib/lrama/grammar/rule.rb', line 3

def rhs
  @rhs
end

Instance Method Details

#as_comment ⇒ Object

Used by #user_actions



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# File 'lib/lrama/grammar/rule.rb', line 13

def as_comment
  l = lhs.id.s_value
  r = rhs.empty? ? "%empty" : rhs.map(&:display_name).join(" ")

  "#{l}: #{r}"
end

#empty_rule? ⇒ Boolean

opt_nl: ε <– empty_rule

| '\n'  <-- not empty_rule



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# File 'lib/lrama/grammar/rule.rb', line 22

def empty_rule?
  rhs.empty?
end

#initial_rule? ⇒ Boolean 



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# File 'lib/lrama/grammar/rule.rb', line 30

def initial_rule?
  id == 0
end

#precedence ⇒ Object 



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# File 'lib/lrama/grammar/rule.rb', line 26

def precedence
  precedence_sym&.precedence
end

#to_s ⇒ Object

TODO: Change this to display_name



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# File 'lib/lrama/grammar/rule.rb', line 5

def to_s
  l = lhs.id.s_value
  r = rhs.empty? ? "ε" : rhs.map {|r| r.id.s_value }.join(", ")

  "#{l} -> #{r}"
end

#translated_code ⇒ Object 



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# File 'lib/lrama/grammar/rule.rb', line 34

def translated_code
  code&.translated_code
end