Method: Q#_nt_negative

Defined in:

lib/q/parser.rb

#_nt_negative ⇒ Object

# File 'lib/q/parser.rb', line 1571

def _nt_negative
  start_index = index
  if node_cache[:negative].has_key?(index)
    cached = node_cache[:negative][index]
    if cached
      node_cache[:negative][index] = cached = SyntaxNode.new(input, index...(index + 1)) if cached == true
      @index = cached.interval.end
    end
    return cached
  end

  i0, s0 = index, []
  if (match_len = has_terminal?('-', false, index))
    r1 = true
    @index += match_len
  else
    terminal_parse_failure('-')
    r1 = nil
  end
  s0 << r1
  if r1
    s2, i2 = [], index
    loop do
      r3 = _nt_ws
      if r3
        s2 << r3
      else
        break
      end
    end
    r2 = instantiate_node(SyntaxNode,input, i2...index, s2)
    s0 << r2
    if r2
      r4 = _nt_primary
      s0 << r4
    end
  end
  if s0.last
    r0 = instantiate_node(SyntaxNode,input, i0...index, s0)
    r0.extend(Negative0)
    r0.extend(Negative1)
  else
    @index = i0
    r0 = nil
  end

  node_cache[:negative][start_index] = r0

  r0
end