src/client/auth/auth.go
func IsErrTooShortTTL(err error) bool {
	if err == nil {
		return false
	}
	errMsg := err.Error()
	return strings.Contains(errMsg, "provided TTL (") &&
		strings.Contains(errMsg, ") is shorter than token's existing TTL (") &&
		strings.Contains(errMsg, ")")
}
func IsErrTooShortTTL(err error) bool {
	if err == nil {
		return false
	}
	errMsg := err.Error()
	return strings.Contains(errMsg, "provided TTL (") &&
		strings.Contains(errMsg, ") is shorter than token's existing TTL (") &&
		strings.Contains(errMsg, ")")
}
// IsErrTooShortTTL returns true if 'err' is a ErrTooShortTTL