bug#47677: [PATCH] condition-case success continuation

[Mattias Engdegård]

26 apr. 2021 kl. 17.12 skrev Filipp Gunbin <fgunbin@fastmail.fm>:

> Please, let's not add such features to the basic Emacs Lisp constructs.
> It's great to see Emacs Lisp being simple.

I'd like to clear up some misconceptions here. (Filipp, this does not mean that 
I think that you wrote something stupid -- quite the contrary.) 

First, is Emacs Lisp really simple? Yes and no. It's not easy to tell where its 
boundaries are, especially since it doesn't have a proper module or namespace 
system or a well-defined 'core language'. Basic semantics -- control 
structures, built-in types, primitives and so on -- are not too messy but 
definitely more than they need to be; Scheme it is not. No wonder given its 
age; it has held up remarkably well considering, but it would be even more 
remarkable if modern eyes could not find flaws in it.

Second, is simplicity paramount among concerns? Clearly not: compatibility 
matters, and so does programming usability. It is also not clear whether a 
change makes a language more or less simple; adding bignums, for example, 
probably made the language less complex for the user. Even if (hypothetically) 
people got by without `unwind-protect` by catching and re-raising errors, few 
would object to adding that construct as a special form because it made the 
language less simple.

Of course you were talking about changes that make the language more difficult 
to use, but my point is that it is far from clear what kind of change actually 
does that.

Unrelated to your comment: since several people have misunderstood the 
proposal, I'm closing the bug to avoid conflating issues (I should have 
listened to Stefan Kangas); a new one can be reopened for the patch at hand 
when and if I get more free time.