rust-coding-guidelines

name	rust-coding-guidelines
description	50 core Rust coding conventions covering naming, data types, strings, error handling, memory, concurrency, async, and modern crate recommendations. Use when reviewing code style or setting up project conventions.

Rust Coding Guidelines

Naming (Rust-Specific)

Rule	Guideline
No get_ prefix	fn name() not fn get_name()
Iterator convention	iter() / iter_mut() / into_iter()
Conversion naming	as_ (cheap ref), to_ (expensive), into_ (ownership)
Constants	SCREAMING_SNAKE_CASE for const/static

Data Types

Rule	Guideline
Use newtypes	struct Email(String) for domain semantics
Prefer slice patterns	if let [first, .., last] = slice
Pre-allocate	Vec::with_capacity(), String::with_capacity()
Avoid Vec abuse	Use arrays for fixed sizes

Strings

Rule	Guideline
Prefer bytes	s.bytes() over s.chars() when ASCII
Use Cow<str>	When might modify borrowed data
Use write!	Over string concatenation with +
Avoid nested iteration	contains() on string is O(n·m)

Error Handling

Rule	Guideline
Use ? propagation	Not try!() macro
expect() over unwrap()	When value is guaranteed
Assertions for invariants	assert! at function entry

Memory

Rule	Guideline
Meaningful lifetimes	'src, 'ctx not just 'a
try_borrow() for RefCell	Avoid panic
Shadowing for transformation	let x = x.parse()?

Concurrency

Rule	Guideline
Identify lock ordering	Prevent deadlocks
Atomics for primitives	Not Mutex for bool/usize
Choose memory order carefully	Relaxed/Acquire/Release/SeqCst

Async

Rule	Guideline
Sync threads for CPU-bound	Async is for I/O
Don't hold locks across await	Use scoped guards

Macros

Rule	Guideline
Avoid unless necessary	Prefer functions/generics
Follow Rust syntax	Macro input should look like Rust

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Deprecated → Better

Deprecated	Better	Since
lazy_static!	std::sync::OnceLock	Rust 1.70
once_cell::Lazy	std::sync::LazyLock	Rust 1.80
std::sync::mpsc	crossbeam::channel	—
std::sync::Mutex	parking_lot::Mutex	—
failure/error-chain	thiserror/anyhow	—
try!()	? operator	2018 edition

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Quick Reference

Naming:  snake_case (fn/var), CamelCase (type), SCREAMING_CASE (const)
Format:  rustfmt (just use it)
Docs:    /// for public items, //! for module docs
Lint:    #![warn(clippy::all)]

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Related Skills

• anti-patterns — common style mistakes
• error-handling — error crate selection
• concurrency — lock ordering and atomics