diff options
| -rw-r--r-- | src/librustc_resolve/diagnostics.rs | 46 |
1 files changed, 45 insertions, 1 deletions
diff --git a/src/librustc_resolve/diagnostics.rs b/src/librustc_resolve/diagnostics.rs index 8a196768ae5..0a8fce49ebb 100644 --- a/src/librustc_resolve/diagnostics.rs +++ b/src/librustc_resolve/diagnostics.rs @@ -948,6 +948,51 @@ use something_which_doesnt_exist; Please verify you didn't misspell the import's name. "##, +E0434: r##" +This error indicates that a variable usage inside an inner function is invalid +because the variable comes from a dynamic environment. Inner functions do not +have access to their containing environment. + +Example of erroneous code: + +```compile_fail +fn foo() { + let y = 5; + fn bar() -> u32 { + y // error: can't capture dynamic environment in a fn item; use the + // || { ... } closure form instead. + } +} +``` + +Functions do not capture local variables. To fix this error, you can replace the +function with a closure: + +``` +fn foo() { + let y = 5; + let bar = || { + y + }; +} +``` + +or replace the captured variable with a constant or a static item: + +``` +fn foo() { + static mut X: u32 = 4; + const Y: u32 = 5; + fn bar() -> u32 { + unsafe { + X = 3; + } + Y + } +} +``` +"##, + E0435: r##" A non-constant value was used to initialise a constant. Example of erroneous code: @@ -1044,5 +1089,4 @@ register_diagnostics! { E0421, // unresolved associated const E0427, // cannot use `ref` binding mode with ... E0429, // `self` imports are only allowed within a { } list - E0434, // can't capture dynamic environment in a fn item } |