code: func (p *Parser) parseColonDefault() (Revisioner, error) {
  	var tok token
  	var lit string
  	var path string
  	var stage int
  	var err error
  	var n = -1
  
  	tok, lit, err = p.scan()
  
  	if err != nil {
  		return nil, err
  	}
  
  	nextTok, _, err := p.scan()
  
  	if err != nil {
  		return nil, err
  	}
  
  	if tok == number && nextTok == colon {
  		n, _ = strconv.Atoi(lit)
  	}
  
  	switch n {
  	case 0, 1, 2, 3:
  		stage = n
  	default:
  		path += lit
  		p.unscan()
  	}
  
  	for {
  		tok, lit, err = p.scan()
  
  		if err != nil {
  			return nil, err
  		}
  
  		switch {
  		case tok == eof && n == -1:
  			return ColonPath{path}, nil
  		case tok == eof:
  			return ColonStagePath{path, stage}, nil
  		default:
  			path += lit
  		}
  	}
  }
docs: // parseColonDefault extract :<data> statements