RS.CLIPPY.CAST_ENUM_TRUNCATION

Casts from an enum type to an integral type that will truncate the value

This checker is a Clippy lint created by The Rust Project Contributors. The documentation shown here is a copy of the original documentation for: cast_enum_truncation. Copyright ©2025 The Rust Team. All rights reserved.

What it does

Checks for casts from an enum type to an integral type that will definitely truncate the value.

Why is this bad?

The resulting integral value will not match the value of the variant it came from.

Example

enum E { X = 256 };
let _ = E::X as u8;