func (x *Lexer) next() rune {
	if x.pos >= len(x.input) {
		x.width = 0
		return eof
	}
	r, w := utf8.DecodeRune(x.input[x.pos:])
	x.width = w
	x.pos += x.width
	return r
}
// next returns the next rune in the input.  If there is a problem decoding
// the rune, then utf8.RuneError is returned.
next returns the next rune in the input.  If there is a problem decoding
the rune, then utf8.RuneError is returned.
// next returns the next rune in the input . If there is a problem decoding // the rune then utf8 . RuneError is returned .
func (x *Lexer) next() rune {
	if x.pos >= len(x.input) {
		x.width = 0
		return eof
	}
	r, w := utf8.DecodeRune(x.input[x.pos:])
	x.width = w
	x.pos += x.width
	return r
}
func ( x * Lexer ) next ( ) rune { if x . pos >= len ( x . input ) { x . width = 0 return eof } r , w := utf8 . DecodeRune ( x . input [ x . pos : ] ) x . width = w x . pos += x . width return r }
next returns the next rune in the input.
next returns the next rune in the input .