rustup doc <topic>

Open the documentation for the current toolchain


topicTopic such as 'core', 'fn', 'usize', 'eprintln!', 'core::arch', 'alloc::format!', 'std::fs', 'std::fs::read_dir', 'std::io::Bytes', 'std::iter::Sum', 'std::io::error::Result' etc


--allocThe Rust core allocation and collections library
--bookThe Rust Programming Language book
--cargoThe Cargo Book
--coreThe Rust Core Library
--edition-guideThe Rust Edition Guide
--embedded-bookThe Embedded Rust Book
-h, --helpPrints help information
--nomiconThe Dark Arts of Advanced and Unsafe Rust Programming
--pathOnly print the path to the documentation
--proc_macroA support library for macro authors when defining new macros
--referenceThe Rust Reference
--rust-by-exampleA collection of runnable examples that illustrate various Rust concepts and standard libraries
--rustcThe compiler for the Rust programming language
--rustdocGenerate documentation for Rust projects
--stdStandard library API documentation
--testSupport code for rustc's built in unit-test and micro-benchmarking framework
--toolchain <toolchain>Toolchain name