Add derive module (#290)

Resolves
#259 (comment)

Add `derive_more::derive` module, re-exporting macros only.

CHANGELOG.md

@@ -52,6 +52,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
   ([#206](https://github.com/JelteF/derive_more/pull/206))
 - Add support for container format in `Debug` derive with the same syntax as `Display` derives.
   ([#279](https://github.com/JelteF/derive_more/pull/279))
+- `derive_more::derive` module exporting only macros, without traits. ([#290](https://github.com/JelteF/derive_more/pull/290))
 
 ### Changed
 

src/lib.rs

@@ -57,6 +57,14 @@ pub mod __private {
     pub use crate::vendor::thiserror::aserror::AsDynError;
 }
 
+/// Module containing macro definitions only, without corresponding traits.
+///
+/// Use it in your import paths, if you don't want to import traits, but only macros.
+pub mod derive {
+    #[doc(inline)]
+    pub use derive_more_impl::*;
+}
+
 // The modules containing error types and other helpers.
 
 #[cfg(feature = "add")]