code: func (loc *Location) unmatchedLines(re *regexp.Regexp) []Line {
  	var lines []Line
  	for _, ln := range loc.Line {
  		if fn := ln.Function; fn != nil {
  			if re.MatchString(fn.Name) {
  				continue
  			}
  			if re.MatchString(fn.Filename) {
  				continue
  			}
  		}
  		lines = append(lines, ln)
  	}
  	return lines
  }
docs: // unmatchedLines returns the lines in the location that do not match
  // the regular expression.