SHA3Digest constructor
      
      SHA3Digest([ 
    
    
- int? bitLength = 288
Implementation
SHA3Digest([int? bitLength = 288]) {
  switch (bitLength) {
    case 224:
    case 256:
    case 384:
    case 512:
      init(bitLength!);
      break;
    default:
      throw StateError(
          'invalid bitLength ($bitLength) for SHA-3 must only be 224,256,384,512');
  }
}