Eric Huss

Fold pattern was confusing to me

8

The [Fold pattern](https://github.com/rust-unofficial/patterns/blob/main/patterns/creational/fold.md) seemed confusing to me. The term "fold" in functional programming has a pretty clear definition (which includes a combining function), and it's not immediately clear from the...

Update special types.

1

I think there are some types missing from special-types-and-traits.md. In particular, I *think* `Fn`, `FnMut`, and `FnOnce` are special. What is the criteria for being special? Is there anything else...

Macro matchers allow `$` as the last token of a token tree: ```rust macro_rules! foo { ($) => {}; (last$) => {}; ({$}) => {}; ([$]) => {}; (($)) =>...

Add "scopes" chapter.

2

This adds the chapter on scopes. I tried to make this accurate and complete, but it is probably neither. There are some things that are intentionally not covered, such as...

Clarify terminology around destructors and dropping

2

In #1037 a question came up about the exact wording around the introduction of the [destructors chapter](https://github.com/rust-lang/reference/blob/0fe357f176673b4bb9a093504a8ae1dcaf4c6f8f/src/destructors.md) which says > When an initialized variable or temporary goes out of scope...

With const generic defaults stabilized (#90207), the reference should talk more about what the restrictions are. * What are valid expressions for the default? I assume it has to be...

From my understanding of https://github.com/rust-lang/rust/pull/89551, constant expressions can now dereference non-mutable raw pointers. I believe [this line](https://github.com/rust-lang/reference/blob/06f9e61931bcf58b91dfe6c924057e42ce273ee1/src/const_eval.md?plain=1#L42) needs updating.

The current page on [`#[non_exhaustive]`](https://github.com/rust-lang/reference/blob/b5c68b02984f74e99d1f1b332029e05f607e2660/src/attributes/type_system.md#the-non_exhaustive-attribute) doesn't really say much about unit structs. I think it could use some clarification. For example, the visibility of the unit struct const is lowered...

There are various places in the grammar that restrict expressions with various types of braces. These restrictions also apply recursively into the expressions. This should be captured somehow. Examples: if-expr.md...

The changes for https://github.com/rust-lang/rust/pull/85769 need to documented (probably around [here](https://github.com/rust-lang/reference/blob/master/src/const_eval.md)). See https://github.com/rust-lang/rust/pull/85769#issuecomment-854363720 for the stabilization report.