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6d19292f16
I've taken some work by @fw-immunant and others on the new organization of the course and condensed it into a form amenable to a text editor and some computational analysis. You can see the inputs in `course.py` but the interesting bits are the output: `outline.md` and `slides.md`. The idea is to break the course into more, smaller segments with exercises at the ends and breaks in between. So `outline.md` lists the segments, their duration, and sums those durations up per-day. It shows we're about an hour too long right now! There are more details of the segments in `slides.md`, or you can see mostly the same stuff in `course.py`. This now contains all of the content from the v1 course, ensuring both that we've covered everything and that we'll have somewhere to redirect every page. Fixes #1082. Fixes #1465. --------- Co-authored-by: Nicole LeGare <dlegare.1001@gmail.com> Co-authored-by: Martin Geisler <mgeisler@google.com>
60 lines
1.3 KiB
Markdown
60 lines
1.3 KiB
Markdown
---
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minutes: 5
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---
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# `break` and `continue`
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If you want to exit any kind of loop early, use
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[`break`](https://doc.rust-lang.org/reference/expressions/loop-expr.html#break-expressions).
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For `loop`, this can take an optional expression that becomes the value of the `loop` expression.
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If you want to immediately start
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the next iteration use [`continue`](https://doc.rust-lang.org/reference/expressions/loop-expr.html#continue-expressions).
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```rust,editable
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fn main() {
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let (mut a, mut b) = (100, 52);
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let result = loop {
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if a == b {
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break a;
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}
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if a < b {
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b -= a;
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} else {
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a -= b;
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}
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};
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println!("{result}");
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}
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```
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Both `continue` and `break` can optionally take a label argument which is used
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to break out of nested loops:
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```rust,editable
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fn main() {
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'outer: for x in 1..5 {
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println!("x: {x}");
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let mut i = 0;
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while i < x {
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println!("x: {x}, i: {i}");
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i += 1;
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if i == 3 {
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break 'outer;
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}
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}
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}
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}
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```
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In this case we break the outer loop after 3 iterations of the inner loop.
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<details>
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* Note that `loop` is the only looping construct which returns a non-trivial
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value. This is because it's guaranteed to be entered at least once (unlike
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`while` and `for` loops).
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</details>
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