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Remove the `From` derive macro from prelude The new `#[derive(From)]` functionality (implemented in https://github.com/rust-lang/rust/pull/144922) caused name resolution ambiguity issues (https://github.com/rust-lang/rust/issues/145524). The reproducer looks e.g. like this: ```rust mod foo { pub use derive_more::From; } use foo::*; #[derive(From)] // ERROR: `From` is ambiguous struct S(u32); ``` It's pretty unfortunate that it works like this, but I guess that there's not much to be done here, and we'll have to wait for the next edition to put the `From` macro into the prelude. That will probably require https://github.com/rust-lang/rust/pull/139493 to land. I created a new module in core (and re-exported it in std) called `from`, where I re-exported the `From` macro. I *think* that since this is a new module, it should not have the same backwards incompatibility issue. Happy to hear suggestions about the naming - maybe it would make sense as `core::macros::from::From`? But we already had a precedent in the `core::assert_matches` module, so I just followed suit. Fixes: https://github.com/rust-lang/rust/issues/145524 r? ``@petrochenkov``