Learning Rust via Advent of Code

Learning Rust via Advent of Code
forrestthewoods.com

> Helper Lambdas

> I like lambdas in C++11. I use them regularly for small helpers that exist solely within a function.

`move` lambdas might work better? The default tries to infer based on usage but often fails. A `move` lambda lets you do something similar to C++'s capture lists (though more verbose / cumbersome).

> BinaryHeap

> The standard library provides a max-heap. I regularly needed a min-heap. I got one by making a custom struct with custom compare function.

std::cmp::Reverse

> I wonder if there is a nice macro crate to help with this? I'd love to write: compare!(a, b, year, month, day, hour, minute);

sort_by_key?

> I wish there was an f16 half-precision float. There's a good internals thread on minifloats that makes me think f16 will happen eventually.

A problem's there is there are at least two "standard" f16 (IEEE and ML)

> There is NonZeroU32. It's similar-ish, but only works for zero. There isn't a Non255U8 or, thankfully, Non4294967296U32.

They're built from the unstable `NonZero` (and the unstable and unsafe ZeroAble).

You could build a struct on top of NonZero which swaps zero and your sentinel value.

These types of problems will give you a good intro to a language, but won't introduce you to the more advanced libraries which you'll likely need in a professional context (e.g. threading/mutexs, tcp/udp, etc).

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