I'm new to rust and I'm trying to do some projects to learn language better. A lot of libraries on crates.io use use library::prelude::* statements. My question is, do I pay compile time cost for importing entire prelude, or just for parts I use in code? Should I import stuff I am using in this file, or should I import entire prelude? In C languages, importing *.h file is attaching header to compile unit, but I can't find info how does it work in Rust.
It's also more robust. Exporting new symbols isn't considered a breaking change for a crate. If those new symbols are the same as ones you're already using from somewhere else, it could cause some minor problems that need to be fixed.