Updated "while let" example.

[androm3da]

No description provided.

[rust-highfive]

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[androm3da]

The text seemed confusing as-is, since it appeared to have no halting condition (are we iterating over "option"?).

[steveklabnik]

@bors: r+ rollup

I agree, this is nicer, thanks.

[bors]

📌 Commit b1c5c26 has been approved by steveklabnik

[brson]

This explanation implies that while let is tied to iterators, which it is not.

[androm3da]

Can you recommend an improvement, or does this mean you think it should stay as-is?

[androm3da]

Proposal: I should restore the original prose and leave the example code as shown.

[steveklabnik]

@brson: ahhh, shucks, reading this, my brain said "while uses an iterator, sure", but while != while let.

@androm3da how about changing it so that the whole example is visible, and remove the temporary?

[steveklabnik]

@bors: r- for now

[androm3da]

@steveklabnik "The temporary" refers to "vec![1, 3, 5, 7, 9, ]"? (sorry, still a bit of a rust newb)

[steveklabnik]

It's all good! I myself made a mistake: when thinking about it, i was thinking this:

let v = vec![1, 3, 5, 7, 9];
while let Some(x) = v.iter() {
    println!("{}", x);
}

but that doesn't work. This should be fine:

let v = vec![1, 3, 5, 7, 9];
let mut iter = v.iter();
while let Some(x) = iter.next() {
    println!("{}", x);
}

[bluss]

should be =, not : on these two lines.

But, why not show off something else than iterators since that's a good while let speciality? For example looping over the result of v.pop().

[bluss]

let mut v = vec![1, 3, 5, 7, 11];
while let Some(x) = v.pop() {
    println!("{}", x);
}

[bluss]

Nice! Thank you

@bors r+ 797a0bd

[bluss]

(A comment on the PR is needed to notify people involved, a pushed commit does not notify, so that's the reason for the two day delay).

[bors]

⌛ Testing commit 797a0bd with merge 3db9bee...

[bors]

☀️ Test successful - auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-debug-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-64-x-android-t, auto-linux-cross-opt, auto-linux-musl-64-opt, auto-mac-32-opt, auto-mac-64-nopt-t, auto-mac-64-opt, auto-win-gnu-32-nopt-t, auto-win-gnu-32-opt, auto-win-gnu-64-nopt-t, auto-win-gnu-64-opt, auto-win-msvc-32-opt, auto-win-msvc-64-opt