decode function
Decodes the given base32-encoded string into an array of 5-bit integers.
Throws ValidationError if input is invalid.
Implementation
Uint8List decode(dynamic string) {
validate(string is String, 'Invalid base32-encoded string: $string.');
final Uint8List data = Uint8List((string as String).length);
for (int i = 0; i < string.length; ++i) {
final String value = string[i];
validate(charsetInverseIndex.containsKey(value), 'Invalid value: $value.');
data[i] = charsetInverseIndex[value]!;
}
return data;
}