ScanIdents     = 1 << -Ident
	ScanInts       = 1 << -Int
	ScanFloats     = 1 << -Float // includes Ints and hexadecimal floats
	ScanChars      = 1 << -Char
	ScanStrings    = 1 << -String
	ScanRawStrings = 1 << -RawString
	ScanComments   = 1 << -Comment
	SkipComments   = 1 << -skipComment // if set with ScanComments, comments become white space
	GoTokens       = ScanIdents | ScanFloats | ScanChars | ScanStrings | ScanRawStrings | ScanComments | SkipComments

	s.Init(r)
	// Newline is like a semicolon; other space characters are fine.
	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,

}

func (p *parser) initScanner(filename string, src io.Reader) {
	p.scanner.Init(src)
	p.scanner.Error = func(_ *scanner.Scanner, msg string) { p.error(msg) }
	p.scanner.Mode = scanner.ScanIdents | scanner.ScanInts | scanner.ScanFloats | scanner.ScanStrings
	p.scanner.Whitespace = 1<<'\t' | 1<<' '
	p.scanner.Filename = filename // for good error messages
	p.next()
}

type importError struct {
	pos scanner.Position
	err error
}

		{"foo0/12/0/5.67", "0 12 0 5 67", ScanInts},
		{"xxx1e0yyy", "1 0", ScanInts},
		{"1_2", "1_2", ScanInts},
		{"xxx1.0yyy2e3ee", "1 0 2 3", ScanInts},
		{"xxx1.0yyy2e3ee", "1.0 2e3", ScanFloats},
	} {
		got := extractInts(test.in, test.mode)
		if got != test.want {
			t.Errorf("%q: got %q; want %q", test.in, got, test.want)
		}
	}
}

func extractInts(t string, mode uint) (res string) {

		{"Position.Filename", Field, 0},
		{"Position.Line", Field, 0},
		{"Position.Offset", Field, 0},
		{"RawString", Const, 0},
		{"ScanChars", Const, 0},
		{"ScanComments", Const, 0},
		{"ScanFloats", Const, 0},
		{"ScanIdents", Const, 0},
		{"ScanInts", Const, 0},
		{"ScanRawStrings", Const, 0},
		{"ScanStrings", Const, 0},
		{"Scanner", Type, 0},
		{"Scanner.Error", Field, 0},

pkg text/scanner, const Int ideal-int
pkg text/scanner, const RawString ideal-int
pkg text/scanner, const ScanChars ideal-int
pkg text/scanner, const ScanComments ideal-int
pkg text/scanner, const ScanFloats ideal-int
pkg text/scanner, const ScanIdents ideal-int
pkg text/scanner, const ScanInts ideal-int
pkg text/scanner, const ScanRawStrings ideal-int
pkg text/scanner, const ScanStrings ideal-int

pkg text/scanner, const Ident = -2
pkg text/scanner, const Int = -3
pkg text/scanner, const RawString = -7
pkg text/scanner, const ScanChars = 32
pkg text/scanner, const ScanComments = 256
pkg text/scanner, const ScanFloats = 16
pkg text/scanner, const ScanIdents = 4
pkg text/scanner, const ScanInts = 8
pkg text/scanner, const ScanRawStrings = 128
pkg text/scanner, const ScanStrings = 64