func IsValidSchemaURI(uri string) bool {
	// TODO more stringent requirements?
	return len(uri) > 0 &&
		utf8.ValidString(uri) &&
		strings.IndexFunc(uri, invalidSchemaRune) == -1
}
// IsValidSchemaURI reports whether the given argument is suitable for
// use as a namespace schema URI. It must be non-empty, a valid UTF-8
// string and it must not contain white space.
IsValidSchemaURI reports whether the given argument is suitable for
use as a namespace schema URI. It must be non-empty, a valid UTF-8
string and it must not contain white space.
// IsValidSchemaURI reports whether the given argument is suitable for // use as a namespace schema URI . It must be non - empty a valid UTF - 8 // string and it must not contain white space .
func IsValidSchemaURI(uri string) bool {
	return len(uri) > 0 &&
		utf8.ValidString(uri) &&
		strings.IndexFunc(uri, invalidSchemaRune) == -1
}
func IsValidSchemaURI ( uri string ) bool { return len ( uri ) > 0 && utf8 . ValidString ( uri ) && strings . IndexFunc ( uri , invalidSchemaRune ) == - 1 }
IsValidSchemaURI reports whether the given argument is suitable for
use as a namespace schema URI.
IsValidSchemaURI reports whether the given argument is suitable for use as a namespace schema URI .
// TODO more stringent requirements?