package fmt
ScanState represents the scanner state passed to custom scanners. Scanners may do rune-at-a-time scanning or ask the ScanState to discover the next space-delimited token.
Golang fmt.ScanState type usage examples
Example 1:
func (z *Int) Scan(s fmt.ScanState, ch rune) error {
s.SkipSpace() // skip leading space characters
...
}
Example 2:
func (z *Rat) Scan(s fmt.ScanState, ch rune) error {
tok, err := s.Token(true, ratTok)
if err != nil {
return err
}
...
Reference :
http://golang.org/pkg/fmt/#ScanState
