ber.go
func isPrintable(b byte) bool {
	return 'a' <= b && b <= 'z' ||
		'A' <= b && b <= 'Z' ||
		'0' <= b && b <= '9' ||
		'\'' <= b && b <= ')' ||
		'+' <= b && b <= '/' ||
		b == ' ' ||
		b == ':' ||
		b == '=' ||
		b == '?' ||
		// This is technically not allowed in a PrintableString.
		// However, x509 certificates with wildcard strings don't
		// always use the correct string type so we permit it.
		b == '*'
}
func isPrintable(b byte) bool {
	return 'a' <= b && b <= 'z' ||
		'A' <= b && b <= 'Z' ||
		'0' <= b && b <= '9' ||
		'\'' <= b && b <= ')' ||
		'+' <= b && b <= '/' ||
		b == ' ' ||
		b == ':' ||
		b == '=' ||
		b == '?' ||
		// This is technically not allowed in a PrintableString.
		// However, x509 certificates with wildcard strings don't
		// always use the correct string type so we permit it.
		b == '*'
}
// isPrintable reports whether the given b is in the ASN.1 PrintableString set.