# Variadic generics - pre-RFC

**URL:** <https://internals.rust-lang.org/t/variadic-generics-pre-rfc/8619>\
**Category:** language design\
**Created:** [October 19, 2018, 12:34pm UTC](https://internals.rust-lang.org/t/variadic-generics-pre-rfc/8619 "2018-10-19T12:34:26Z")\
**Posts on this page:** 1\
**Showing post:** 14

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**Author:** ![RustyYato](https://sea2.discourse-cdn.com/flex002/user_avatar/internals.rust-lang.org/rustyyato/32/13627_2.png) [@RustyYato](https://internals.rust-lang.org/u/RustyYato)\
**Post date:** [October 19, 2018, 5:21pm UTC](https://internals.rust-lang.org/t/variadic-generics-pre-rfc/8619/14 "2018-10-19T17:21:20Z")

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We don’t have generic associated types yet, and if and when we do get them we will have where bounds on associated types. Therefore, bounds on tuple types could be defined earlier in the impl using where bounds.

```rust
impl<*T> Trait for Foo<T>
where T: Clone {
   type Assoc = T;
}

```

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_[View the full topic](https://internals.rust-lang.org/t/variadic-generics-pre-rfc/8619)._