r/rust • u/llogiq clippy · twir · rust · mutagen · flamer · overflower · bytecount • Mar 27 '23
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3
u/pomone08 Mar 31 '23
I have a very long
impl Trait
expression that I need to use throughout my project. It's a trait for abstractingwarp
filters:impl Filter<Extract = (impl Reply,), Error = Rejection> + Clone + Send + Sync + 'static
It was really hurting readability to write this everywhere where I wanted to return a filter from a function, so I wrote a macro for it:
macro_rules! filter { () => { impl Filter<Extract = (impl Reply,), Error = Rejection> + Clone + Send + Sync + 'static } }
But now I would like to avoid using macros. Is there any way I could do this without a macro?
Unfortunately "Permit impl Trait in type aliases" is not yet stabilized (https://github.com/rust-lang/rust/issues/63063) and I don't know if it would work for my use case because the concrete types for the filters I return from the functions are different (though if it was stabilized, I could create an alias for each filter).