Anyhow Rust

Use these conventions for Rust error handling with dtolnay/anyhow. Anyhow provides anyhow::Error, a trait-object error type that wraps anything implementing std::error::Error, plus ergonomic context, chaining, and downcasting.

Source Baseline

• Prefer released docs from docs.rs/anyhow, crates.io, and the matching GitHub release over older blog snippets.
• Latest 1.x release line. Add to Cargo.toml:

  [dependencies]
  anyhow = "1"
  

• For no-std: anyhow = { version = "1", default-features = false }. A global allocator is still required.

Application vs Library Split

This is the most important rule. Pick the right tool at the right boundary: