### What it does Checks for `match` expressions modifying the case of a string with non-compliant arms ### Why is this bad? The arm is unreachable, which is likely a mistake ### Example ``` match &*text.to_ascii_lowercase() { "foo" => {}, "Bar" => {}, _ => {}, } ``` Use instead: ``` match &*text.to_ascii_lowercase() { "foo" => {}, "bar" => {}, _ => {}, } ```