diff options
| -rw-r--r-- | src/librustc/diagnostics.rs | 45 |
1 files changed, 44 insertions, 1 deletions
diff --git a/src/librustc/diagnostics.rs b/src/librustc/diagnostics.rs index 6e94ac83d55..6c0a2eb381c 100644 --- a/src/librustc/diagnostics.rs +++ b/src/librustc/diagnostics.rs @@ -1899,6 +1899,50 @@ contain references (with a maximum lifetime of `'a`). [1]: https://github.com/rust-lang/rfcs/pull/1156 "##, +E0400: r##" +A user-defined dereference was attempted in an invalid context. Erroneous +code example: + +``` +use std::ops::Deref; + +struct A; + +impl Deref for A { + type Target = str; + + fn deref(&self)-> &str { "foo" } +} + +const S: &'static str = &A; +// error: user-defined dereference operators are not allowed in constants + +fn main() { + let foo = S; +} +``` + +You cannot directly use a dereference operation whilst initializing a constant +or a static. To fix this error, restructure your code to avoid this dereference, +perharps moving it inline: + +``` +use std::ops::Deref; + +struct A; + +impl Deref for A { + type Target = str; + + fn deref(&self)-> &str { "foo" } +} + +fn main() { + let foo : &str = &A; +} +``` +"##, + E0492: r##" A borrow of a constant containing interior mutability was attempted. Erroneous code example: @@ -2175,7 +2219,6 @@ register_diagnostics! { E0314, // closure outlives stack frame E0315, // cannot invoke closure outside of its lifetime E0316, // nested quantification of lifetimes - E0400, // overloaded derefs are not allowed in constants E0452, // malformed lint attribute E0453, // overruled by outer forbid E0471, // constant evaluation error: .. |