imho the most valuable vote for mandatory self, just one comment on it
> 1) Accessing a property, in a class, is more expensive than accessing a local
> variable. The above code would require three message sends and/or vtable
> accesses instead of one, if it were not assigning the property to a local
> variable. These unnecessary property accesses needlessly reduce the
> efficiency of the program.
True for Objective-C, and might be true for Swift in many cases as well - but
just because of legacy reasons:
Correct me if I'm wrong, but I expect that simple getters have no performance
penalty at all.
Nonetheless, you can't see how expensive the access is, and the effects in
multi-threaded environments are a real issue - but those two reasons are no
argument for mandatory self, but rather against it:
When there are issues with repetitive access, you can just insert a "let foo =
self.foo", and the problem is gone; you can't do so when you already referenced
the variable with "self.foo" all over the place.
This is imho one of the most important lessons to learn from this thread:
Just don't give your variables confusing names, unless you have good reason to
do so!
Best regards,
Tino
p.s.:
I've have read an article that advises not to cache getters at all - but
couldn't remember or search a reference for this. Afair the proposal came from
a Java-background - which fits to my memory that the possible performance
problems weren't addressed ;-)
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