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Remove language about an experiment 

Some of the language in this RFC implied that this is an experiment
and that another RFC would be required.  This isn't how we want to
frame things.  Another RFC could always be required, but it's also
possible that stabilization could occur on the basis of this RFC.

This is a normal RFC.  Let's remove all language about this being an
experiment.
This commit is contained in:
Travis Cross 2023-10-18 16:50:38 +00:00
parent c982935b9d
commit ffcf8811e5
1 changed files with 9 additions and 12 deletions
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text/0000-gen-fn.md
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@ -6,9 +6,7 @@
# Summary
[summary]: #summary
Reserve the `gen` keyword in the 2024 edition and start experimenting on
implementing generator functions and blocks that allow implementing `Iterator`s
without writing `Iterator::next` impls under placeholder syntax.
Reserve the `gen` keyword in the 2024 edition.
Add `gen {}` blocks to the language. These implement `Iterator` by `yield`ing
elements. This is simpler and more intuitive than creating a custom type and
@ -23,11 +21,12 @@ Furthermore, add `gen fn` to the language. `gen fn foo(arg: X) -> Y` desugars to
# Motivation
[motivation]: #motivation
The main motivation of this RFC is to reserve a new keyword in the 2024 edition.
The feature used by the keyword described here should be treated as an e-RFC for
experimentation on nightly. I would like to avoid discussion of the semantics
provided here, deferring that discussion until during the experimental
implementation work.
The main motivation of this RFC is to reserve a new keyword in the 2024
edition. We will discuss the semantic questions of generators in this
document, but we do not have to settle them with this RFC. We'll describe
current thinking on the semantics, but some questions will be left open to be
answered at a later time after we gain more experience with the
implementation.
Writing iterators manually can be very painful. Many iterators can be written by
chaining `Iterator` methods, but some need to be written as a `struct` and have
@ -280,10 +279,8 @@ gen fn foo() {}
## Different syntax for `gen fn`:
This RFC explicitly picks an attribute, as that has no conflicts with any other syntax, even within macros, and
does not pick any option that may influence how experimental users think about syntax.
There are many options to choose from, and we'll have to decide on one before stabilization.
Some options are:
This RFC selects `gen` as the keyword. But there are other options we might
pick. Here are some alternatives:
```rust
fn foo(args) yield item