Static rustc_lint_defs::builtin::BINDINGS_WITH_VARIANT_NAME

pub static BINDINGS_WITH_VARIANT_NAME: &'static Lint

The bindings_with_variant_name lint detects pattern bindings with the same name as one of the matched variants.

Example

pub enum Enum {
    Foo,
    Bar,
}

pub fn foo(x: Enum) {
    match x {
        Foo => {}
        Bar => {}
    }
}

{{produces}}

Explanation

It is usually a mistake to specify an enum variant name as an identifier pattern. In the example above, the match arms are specifying a variable name to bind the value of x to. The second arm is ignored because the first one matches all values. The likely intent is that the arm was intended to match on the enum variant.

Two possible solutions are:

• Specify the enum variant using a path pattern, such as Enum::Foo.
• Bring the enum variants into local scope, such as adding use Enum::*; to the beginning of the foo function in the example above.