diff options
Diffstat (limited to 'compiler/rustc_error_codes/src/error_codes/E0478.md')
| -rw-r--r-- | compiler/rustc_error_codes/src/error_codes/E0478.md | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/compiler/rustc_error_codes/src/error_codes/E0478.md b/compiler/rustc_error_codes/src/error_codes/E0478.md new file mode 100644 index 000000000..4bc5fde2e --- /dev/null +++ b/compiler/rustc_error_codes/src/error_codes/E0478.md @@ -0,0 +1,28 @@ +A lifetime bound was not satisfied. + +Erroneous code example: + +```compile_fail,E0478 +// Check that the explicit lifetime bound (`'SnowWhite`, in this example) must +// outlive all the superbounds from the trait (`'kiss`, in this example). + +trait Wedding<'t>: 't { } + +struct Prince<'kiss, 'SnowWhite> { + child: Box<Wedding<'kiss> + 'SnowWhite>, + // error: lifetime bound not satisfied +} +``` + +In this example, the `'SnowWhite` lifetime is supposed to outlive the `'kiss` +lifetime but the declaration of the `Prince` struct doesn't enforce it. To fix +this issue, you need to specify it: + +``` +trait Wedding<'t>: 't { } + +struct Prince<'kiss, 'SnowWhite: 'kiss> { // You say here that 'SnowWhite + // must live longer than 'kiss. + child: Box<Wedding<'kiss> + 'SnowWhite>, // And now it's all good! +} +``` |