Class: Fabulator::Grammar::Expr::LookAhead

Inherits:
Object
  • Object
show all
Defined in:
lib/fabulator/grammar/expr/look_ahead.rb

Instance Method Summary collapse

Constructor Details

#initialize(sequence) ⇒ LookAhead

Returns a new instance of LookAhead.



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# File 'lib/fabulator/grammar/expr/look_ahead.rb', line 5

def initialize(sequence)
  @sequence = sequence
end

Instance Method Details

#name ⇒ Object 



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# File 'lib/fabulator/grammar/expr/look_ahead.rb', line 9

def name
  nil
end

#parse(source) ⇒ Object

Raises:



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# File 'lib/fabulator/grammar/expr/look_ahead.rb', line 13

def parse(source)
  ret = false
  source.attempt do |c|
    ret = @sequence.parse(c)
    raise Fabulator::Grammar::RejectParse
  end
  raise Fabulator::Grammar::RejectParse unless ret
end