Class: Racc::Sym

Inherits:
Object show all
Defined in:
lib/racc/grammar.rb

Overview

Stands terminal and nonterminal symbols.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(value, dummyp) ⇒ Sym

Returns a new instance of Sym.



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# File 'lib/racc/grammar.rb', line 1051

def initialize(value, dummyp)
  @ident = nil
  @value = value
  @dummyp = dummyp

  @term  = nil
  @nterm = nil
  @should_terminal = false
  @precedence = nil
  case value
  when Symbol
    @to_s = value.to_s
    @serialized = value.inspect
    @string = false
  when String
    @to_s = value.inspect
    @serialized = value.dump
    @string = true
  when false
    @to_s = '$end'
    @serialized = 'false'
    @string = false
  else
    raise ArgumentError, "unknown symbol value: #{value.class}"
  end

  @heads    = []
  @locate   = []
  @snull    = nil
  @null     = nil
  @expand   = nil
  @useless  = nil
end

Instance Attribute Details

#assoc ⇒ Object

Returns the value of attribute assoc.



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# File 'lib/racc/grammar.rb', line 1141

def assoc
  @assoc
end

#expand ⇒ Object (readonly)

Returns the value of attribute expand.



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# File 'lib/racc/grammar.rb', line 1178

def expand
  @expand
end

#heads ⇒ Object (readonly)

cache



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# File 'lib/racc/grammar.rb', line 1161

def heads
  @heads
end

#ident ⇒ Object (readonly) Also known as: hash

Returns the value of attribute ident.



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# File 'lib/racc/grammar.rb', line 1098

def ident
  @ident
end

#locate ⇒ Object (readonly)

Returns the value of attribute locate.



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# File 'lib/racc/grammar.rb', line 1162

def locate
  @locate
end

#precedence ⇒ Object

Returns the value of attribute precedence.



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# File 'lib/racc/grammar.rb', line 1140

def precedence
  @precedence
end

#serialized=(value) ⇒ Object (writeonly)

Sets the attribute serialized

Parameters:

  • value —

    the value to set the attribute serialized to.



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# File 'lib/racc/grammar.rb', line 1138

def serialized=(value)
  @serialized = value
end

#value ⇒ Object (readonly)

Returns the value of attribute value.



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# File 'lib/racc/grammar.rb', line 1102

def value
  @value
end

Class Method Details

.once_writer(nm) ⇒ Object 



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# File 'lib/racc/grammar.rb', line 1086

def once_writer(nm)
  nm = nm.id2name
  module_eval(<<-EOS)
    def #{nm}=(v)
      raise 'racc: fatal: @#{nm} != nil' unless @#{nm}.nil?
      @#{nm} = v
    end
  EOS
end

Instance Method Details

#dummy? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/racc/grammar.rb', line 1104

def dummy?
  @dummyp
end

#nonterminal? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/racc/grammar.rb', line 1112

def nonterminal?
  @nterm
end

#null=(n) ⇒ Object 



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# File 'lib/racc/grammar.rb', line 1174

def null=(n)
  @null = n
end

#nullable? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/racc/grammar.rb', line 1170

def nullable?
  @null
end

#rule ⇒ Object 



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# File 'lib/racc/grammar.rb', line 1153

def rule
  Rule.new(nil, [self], UserAction.empty)
end

#self_null? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/racc/grammar.rb', line 1164

def self_null?
  @snull
end

#serialize ⇒ Object 



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# File 'lib/racc/grammar.rb', line 1134

def serialize
  @serialized
end

#should_terminal ⇒ Object 



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# File 'lib/racc/grammar.rb', line 1122

def should_terminal
  @should_terminal = true
end

#should_terminal? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/racc/grammar.rb', line 1126

def should_terminal?
  @should_terminal
end

#string_symbol? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/racc/grammar.rb', line 1130

def string_symbol?
  @string
end

#term=(t) ⇒ Object 



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# File 'lib/racc/grammar.rb', line 1116

def term=(t)
  raise 'racc: fatal: term= called twice' unless @term.nil?
  @term = t
  @nterm = !t
end

#terminal? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/racc/grammar.rb', line 1108

def terminal?
  @term
end

#to_s ⇒ Object Also known as: inspect 



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# File 'lib/racc/grammar.rb', line 1143

def to_s
  @to_s.dup
end

#useless=(f) ⇒ Object 



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# File 'lib/racc/grammar.rb', line 1185

def useless=(f)
  @useless = f
end

#useless? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/racc/grammar.rb', line 1181

def useless?
  @useless
end

#|(x) ⇒ Object 



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# File 'lib/racc/grammar.rb', line 1149

def |(x)
  rule() | x.rule
end