Class: Dhaka::LexerSupport::DFARun

Inherits:
Object
  • Object
show all
Defined in:
lib/dhaka/lexer/dfa.rb

Instance Method Summary collapse

Constructor Details

#initialize(dfa, input) ⇒ DFARun

Returns a new instance of DFARun.



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# File 'lib/dhaka/lexer/dfa.rb', line 89

def initialize(dfa, input)
  @dfa, @input = dfa, input
  @matched = ""
  @not_yet_accepted = ""
  @curr_state = @dfa.start_state
end

Instance Method Details

#accept(pattern) ⇒ Object 



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# File 'lib/dhaka/lexer/dfa.rb', line 110

def accept(pattern)
  @matched.concat @not_yet_accepted
  @not_yet_accepted = ""
end

#accept_last_saved_checkpoint(pattern) ⇒ Object 



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# File 'lib/dhaka/lexer/dfa.rb', line 115

def accept_last_saved_checkpoint(pattern)
  @matched = @last_saved_checkpoint
  @not_yet_accepted = ""
end

#match ⇒ Object 



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# File 'lib/dhaka/lexer/dfa.rb', line 96

def match
  @input.unpack("C*").each do |i|
    break unless dest_state = @curr_state.transitions[i.chr]
    @not_yet_accepted << i.chr
    @curr_state = dest_state
    @curr_state.process(self)
  end
  @matched
end

#save_checkpoint(pattern) ⇒ Object 



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# File 'lib/dhaka/lexer/dfa.rb', line 106

def save_checkpoint(pattern)
  @last_saved_checkpoint = @matched + @not_yet_accepted
end