// stepByte steps runq to nextq consuming c and then expanding according to flag.
// It returns true if a match ends immediately before c.
// c is either an input byte or endText.
func (m *matcher) stepByte(runq, nextq *sparse.Set, c int, flag syntax.EmptyOp) (match bool) {
nextq.Reset()
m.addq(nextq, uint32(m.prog.Start), flag)
for _, id := range runq.Dense() {
i := &m.prog.Inst[id]
switch i.Op {
default:
continue
case syntax.InstMatch:
match = true
continue
case instByteRange:
if c == endText {
break
}
lo := int((i.Arg >> 8) & 0xFF)
hi := int(i.Arg & 0xFF)
ch := c
if i.Arg&argFold != 0 && 'a' <= ch && ch <= 'z' {
ch += 'A' - 'a'
}
if lo <= ch && ch <= hi {
m.addq(nextq, i.Out, flag)
}
}
}
return
}
// stepEmpty steps runq to nextq expanding according to flag.
func (m *matcher) stepEmpty(runq, nextq *sparse.Set, flag syntax.EmptyOp) {
nextq.Reset()
for _, id := range runq.Dense() {
m.addq(nextq, id, flag)
}
}