[swift-evolution] Proposal: 0009 Require self for accessing instance members

me at michael-brown.net me at michael-brown.net
Thu Dec 17 11:28:01 CST 2015

On Tue, Dec 15, 2015 at 21:03 Sune Foldager via swift-evolution <swift-evolution at swift.org> wrote:

> Personally, I am against using mandatory self. I have coded a lot of Python, and I find it quite annoying to have to type (and read) “self.” everywhere. It’s a balance, of course:
> “self.” everywhere means you can see what’s an instance member and what’s a local variable. That’s generally a good thing. But it also means a lot of filler text in your code, which makes reading and writing slower. That’s not so good. It’s a balance, and in this case my experience from C# (and, as mentioned, Python) is that I much prefer C#’s non-mandatory use of “this”/“self".
> I see that this proposal is going to be reviewed as SE-0009, and I am a bit concerned that not all arguments are being considered because of the contents of the proposal text: The only counter argument mentioned in the proposal has to do with capturing semantics in closures. This is fine, but why isn’t the counter argument of verbosity being mentioned? This has been brought up on the list as well.
> Also, the “Community Responses” section exclusively lists positive feedback. Is that how it’s supposed to be with the SE process? If not, where are the arguments from people who are -1 on the proposal?
> I really hope the review team considers:
> - The negative responses on this list as well. Also consider that many Swift developers are not on this list; I doubt it’s representative, either, being dominated by “language interested” developers.
> - The rather large amount of changes to existing code required.

I couldn't agree more on all points. I strongly object to this proposal. Requiring self makes code unnecessarily verbose and is one of the things I least liked about Objective-C compared to other languages (e.g. C#, Python, Java) where the use of self/this is optional. It is only only actually necessary when resolving ambiguity with local variables, in the few situations where such ambiguity exists (initialisers mostly).

The use of self for accessing instance members is a question of coding style, and should not be made mandatory by the language. If the supporters of this proposal want to use self everywhere, then they are quite free to do so, but please don't force this on everyone!


More information about the swift-evolution mailing list