Richard I don't think so. The case being considered for my problem is the compression of a ByteArray produced by applying #utf8Encoded to a WideString, but it extends to any other form of ByteArray. If you substitute ByteArray for SomeClass in your examples, I think you will see why the chosen interface was used.
Peter Kenny -----Original Message----- From: Pharo-users <pharo-users-boun...@lists.pharo.org> On Behalf Of Richard O'Keefe Sent: 03 October 2019 23:08 To: Any question about pharo is welcome <pharo-users@lists.pharo.org> Subject: Re: [Pharo-users] How to zip a WideString The interface should surely be SomeClass methods for: 'compression' zipped "return a byte array" class methods for: 'decompression' unzip: aByteArray "return an instance of SomeClass"