As others have said, having a package management system that deeply understands the language and tooling is awesome. Examples:
- Rust has a distributed-by-default documentation generator (rustdoc), cargo knows this and provides `cargo doc` to render a library's docs with it.
- rustdoc can run code examples in the documentation as tests, to check that everything is up-to-date, `cargo test` does this (along with running the in-source unit tests and any external tests).
- the Rust compiler allows for plugins, which are dynamic libraries loaded into the compiler and can be used for things like custom macros (aka procedural macros aka syntax extensions) and custom compiler warnings. cargo understands these, allows them to be 'imported' via the normal dependency mechanism, and specifying `plugin = true` in a package makes cargo do the right thing, e.g. building as a dynamic library (static libraries are the default) and compiling for the correct target when cross-compiling.
I'm sure all of this is possible with other systems, but it seems unlikely to be so nice to use.
It's very similar to Racket, and yes, it is nice to use!
Other systems can get you much of the way there (node, Python are the only ones I'm really familiar with) but I suspect you need a little language help to achieve the same kind of convenience.
- Rust has a distributed-by-default documentation generator (rustdoc), cargo knows this and provides `cargo doc` to render a library's docs with it.
- rustdoc can run code examples in the documentation as tests, to check that everything is up-to-date, `cargo test` does this (along with running the in-source unit tests and any external tests).
- the Rust compiler allows for plugins, which are dynamic libraries loaded into the compiler and can be used for things like custom macros (aka procedural macros aka syntax extensions) and custom compiler warnings. cargo understands these, allows them to be 'imported' via the normal dependency mechanism, and specifying `plugin = true` in a package makes cargo do the right thing, e.g. building as a dynamic library (static libraries are the default) and compiling for the correct target when cross-compiling.
I'm sure all of this is possible with other systems, but it seems unlikely to be so nice to use.