From a2d7c33aa83d39cd0ab1fba0a8ccdfd2c7f29576 Mon Sep 17 00:00:00 2001 From: Ivan Tham Date: Mon, 10 Aug 2020 22:33:17 +0800 Subject: Split fix into another section for E0749 --- src/librustc_error_codes/error_codes/E0749.md | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'src/librustc_error_codes/error_codes') diff --git a/src/librustc_error_codes/error_codes/E0749.md b/src/librustc_error_codes/error_codes/E0749.md index 74cd2903f6d..962da0eda08 100644 --- a/src/librustc_error_codes/error_codes/E0749.md +++ b/src/librustc_error_codes/error_codes/E0749.md @@ -11,10 +11,20 @@ trait MyTrait { impl !MyTrait for u32 { type Foo = i32; // error! } -// impl !MyTrait for u32 {} // fix # fn main() {} ``` Negative impls are not allowed to have any items. Negative impls declare that a trait is **not** implemented (and never will be) and hence there is no need to specify the values for trait methods or other items. + +One way to fix this is to remove the items in negative impls. + +``` +# #![feature(negative_impls)] +trait MyTrait { + type Foo; +} + +impl !MyTrait for u32 {} +``` -- cgit 1.4.1-3-g733a5