I was having a think about this short history of Objective-C, and it occurred to me that perhaps I had been thinking about ObjC wrong. Now, I realise that by thinking about ObjC at all I mark myself out as a bit of an oddball, but I do it a lot. I co-host the [objc retain]; stream with Steven Baker, discussing cross-platform free software Objective-C every week. Hell of a time to realise I’ve been doing it wrong.
My current thinking is that the idea of ObjC is not to write “apps” in ObjC, or even in successor languages (sorry, fans of successor languages). Summed up in that history are Brad Cox’s views which you can read in more length in his books. I’ve at least tangentially covered each book here: Object-Oriented Programming: an Evolutionary Approach and Superdistribution: Objects as Property on the Electronic Frontier. In these he talks about Object-Oriented Programming as the “software industrial revolution”, in which the each-one-is-bespoke way of writing software from artisinally-selected ones and lightly-sparkling zeroes is replaced with a catalogue of re-usable parts, called Software ICs (integrated circuits). As an integrator, I might take the “window” IC, the “button” IC, the “text field” IC, and a “data store” IC and make a board for entering expenses.
So far, so npm. The key bit is the next bit. As a computer owner, you might take that board and integrate it into your computer so that you can do your home finances, or so that you can submit your business expense claims, or so that your characters in The Sims can claim for their CPU time, or all three of those things. The key is that this isn’t some app developer, this is the person whose computer it is.
From that perspective, Objective-C is an intermediary tool, and not a particularly important or long-lasting one. Its job is to turn legacy code into objects so that it can be accessed by people using their computers by sticking software together using objects (hello NSFileManager). To the extent it has an ongoing job, that is to turn algorithms into objects, for the same reason (but the algorithms have been made out of not-objects, because All Hail the Perform Ant).
You can make your software on your computer by glueing objects together, whether they’re made of ObjC (a common and important case), Eiffel (an uncommon and important case), Smalltalk (ditto) or whatever. Objective-C is the shiny surface we’re missing over the tar pit. It is the gear system on the bicycle for the mind; the tool that frees computer users from the tyranny of the app vendor and the app store.
I apologise for taking this long to work that out.
You might call it an architectural adapter.