s.Whitespace = 1<<'\t' | 1<<'\r' | 1<<' '
	// Don't skip comments: we need to count newlines.
	s.Mode = scanner.ScanChars |
		scanner.ScanFloats |
		scanner.ScanIdents |
		scanner.ScanInts |
		scanner.ScanStrings |
		scanner.ScanComments
	s.Position.Filename = name
	s.IsIdentRune = isIdentRune
	return &Tokenizer{
		s:    &s,
		base: src.NewFileBase(name, objabi.AbsFile(objabi.WorkingDir(), name, *flags.TrimPath)),
		line: 1,