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Prelude

As explained in Idiomatic Rust

A prelude module is a Rust module that publicly re-exports commonly used items from a crate.

A prelude module gathers useful crate items in one place, making them easier to import and helping users avoid guessing which symbols they need. section 8.4

Build one with `pub use` statements: they re-export items so code outside the module can import them. A separate `prelude` module keeps these exports distinct from other crate imports. section 8.4

Listing 8.11 Listing for prelude.rs
pub use crate::a::InnerA;
pub use crate::b::InnerB;
pub use crate::TopLevelStruct;

This prelude re-exports items from two crate modules and the crate root; users can then import them through `mylib::prelude`. section 8.4

How Idiomatic Rust covers it

How deep it goes
Explains `pub use`, wildcard imports, and a crate `prelude` module with an implementation example.
Examples
Uses a crate with modules `a` and `b`, re-exporting their items and a top-level struct from `prelude.rs`.
What it assumes
Assumes familiarity with Rust `use` imports and develops public re-exports from that syntax.
What you can do after
Build it from scratch by adding a `prelude` module that publicly re-exports selected crate items.
How it connects
Connects Rust modules, imports, public re-exports, and wildcard imports.
Cover of Idiomatic Rust
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Related concepts

This explainer was generated by Manning's knowledge graph from the text of Idiomatic Rust. The section links point to the parts of the book it draws on.