On Wednesday, October 28, 2015 at 10:22:45 AM UTC+1, Glen O wrote: > > The thing is, it IS an assignment that's going on. In the case of a range, > especially, "for i=1:5" says "loop 5 times, with i=1, then i=2, then i=3, > then i=4, then i=5". "i' is being assigned to on each iteration. Think of > it this way - suppose you were using elementwise operations. You could write > > i=1:5 > A[i]=B[i].*C[i] > > or, you could write it as a loop... > > for i=1:5 > A[i]=B[i]*C[i] > end >
I buy that argument. Both 'in' and '=' make good metaphors for thinking about loops. It's that they are different metaphors, while 'in' and '∈' are identical in meaning and (arguably) in pronunciation. Choosing either of them for loops would be fine, but having two different synonyms for 'in' is just a bit jarring. > The two pieces of code are doing exactly the same thing; one is just > explicitly writing the loop. In what way does restricting to "in" help, in > this situation? > I don't know about this situation in particular, but I think in general it is helping in a) simplifying; no more three-way aliasing stuff. b) consistency; 'in' and '∈' become interchangeable in both contexts.
