unilex/scanners.go
2021-03-06 22:30:32 +03:00

25 lines
639 B
Go

package unilex
// ScanNumber simplest scanner that accepts decimal int and float.
func ScanNumber(l *Lexer) bool {
l.AcceptWhile("0123456789")
if l.AtStart() {
// not found any digit
return false
}
l.Accept(".")
l.AcceptWhile("0123456789")
return !l.AtStart()
}
// ScanAlphaNum returns true if next input token contains alphanum sequence that not starts from digit and not contains.
// spaces or special characters.
func ScanAlphaNum(l *Lexer) bool {
digits := "0123456789"
alpha := "qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM"
if !l.Accept(alpha) {
return false
}
l.AcceptWhile(alpha + digits)
return true
}