}

// Subtag returns the subtag for which the error occurred.
func (e ValueError) Subtag() string {
	return string(e.tag())
}

// scanner is used to scan BCP 47 tokens, which are separated by _ or -.
type scanner struct {
	b     []byte
	bytes [max99thPercentileSize]byte
	token []byte
	start int // start position of the current token
	end   int // end position of the current token

	}
}

// have reports whether the remaining tokens (including the current one) contain the specified token.
func (p *Parser) have(token lex.ScanToken) bool {
	for i := p.inputPos; i < len(p.input); i++ {
		if p.input[i].ScanToken == token {
			return true
		}
	}
	return false
}

// at reports whether the next tokens are as requested.
func (p *Parser) at(next ...lex.ScanToken) bool {