# Mut String += format\_args!(…);

**URL:** <https://internals.rust-lang.org/t/mut-string-format-args/19461>\
**Category:** language design\
**Created:** [September 1, 2023, 9:23am UTC](https://internals.rust-lang.org/t/mut-string-format-args/19461 "2023-09-01T09:23:27Z")\
**Posts on this page:** 1\
**Showing post:** 27

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**Author:** ![Aloso](https://sea2.discourse-cdn.com/flex002/user_avatar/internals.rust-lang.org/aloso/32/5039_2.png) [@Aloso](https://internals.rust-lang.org/u/Aloso)\
**Post date:** [September 5, 2023, 10:28pm UTC](https://internals.rust-lang.org/t/mut-string-format-args/19461/27 "2023-09-05T22:28:13Z")

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Another thread I created a while ago: [Method to append any `Display` type to a String](https://internals.rust-lang.org/t/method-to-append-any-display-type-to-a-string/17070)

I would really prefer an inherent method over a `+=` impl, because

- it is less magical
- it is more general (it can be generic over `Display`, whereas a blanket `impl<T> AddAssign<T> for String where T: Display` is not possible)

In the previous discussion, there were only two open questions: The name, and whether the method should accept `T` or `&T` (though most people argued for `&T`).

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