INVALID_TYPE_PARAM_DEFAULT in rustc_lint::builtin - Rust
Description: The `invalid_type_param_default` lint detects type parameter defaults erroneously allowed in an invalid location.

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## INVALID_TYPE_PARAM_DEFAULT

# Static INVALID_TYPE_PARAM_DEFAULT

Source

    pub static INVALID_TYPE_PARAM_DEFAULT: &'static Lint

Expand description

The `invalid_type_param_default` lint detects type parameter defaults erroneously allowed in an invalid location.

#### §Example

ⓘ

    fn foo<T=i32>(t: T) {}

{{produces}}

#### §Explanation

Default type parameters were only intended to be allowed in certain situations, but historically the compiler allowed them everywhere. This is a future-incompatible lint to transition this to a hard error in the future. See issue #36887 for more details.