rust/tests/ui/closures/coerce-unsafe-to-closure.rs

fn main() {
    let x: Option<&[u8]> = Some("foo").map(std::mem::transmute);
    //~^ ERROR E0277
}
Forbid coercing unsafe functions to closures Closes #9582 2014-01-16 14:20:59 -06:00			`fn main() {`
core: Remove the cast module This commit revisits the `cast` module in libcore and libstd, and scrutinizes all functions inside of it. The result was to remove the `cast` module entirely, folding all functionality into the `mem` module. Specifically, this is the fate of each function in the `cast` module. * transmute - This function was moved to `mem`, but it is now marked as #[unstable]. This is due to planned changes to the `transmute` function and how it can be invoked (see the #[unstable] comment). For more information, see RFC 5 and #12898 * transmute_copy - This function was moved to `mem`, with clarification that is is not an error to invoke it with T/U that are different sizes, but rather that it is strongly discouraged. This function is now #[stable] * forget - This function was moved to `mem` and marked #[stable] * bump_box_refcount - This function was removed due to the deprecation of managed boxes as well as its questionable utility. * transmute_mut - This function was previously deprecated, and removed as part of this commit. * transmute_mut_unsafe - This function doesn't serve much of a purpose when it can be achieved with an `as` in safe code, so it was removed. * transmute_lifetime - This function was removed because it is likely a strong indication that code is incorrect in the first place. * transmute_mut_lifetime - This function was removed for the same reasons as `transmute_lifetime` * copy_lifetime - This function was moved to `mem`, but it is marked `#[unstable]` now due to the likelihood of being removed in the future if it is found to not be very useful. * copy_mut_lifetime - This function was also moved to `mem`, but had the same treatment as `copy_lifetime`. * copy_lifetime_vec - This function was removed because it is not used today, and its existence is not necessary with DST (copy_lifetime will suffice). In summary, the cast module was stripped down to these functions, and then the functions were moved to the `mem` module. transmute - #[unstable] transmute_copy - #[stable] forget - #[stable] copy_lifetime - #[unstable] copy_mut_lifetime - #[unstable] [breaking-change] 2014-05-09 12:34:51 -05:00			`let x: Option<&[u8]> = Some("foo").map(std::mem::transmute);`
Fallout from changing fn traits to use inheritance rather than bridge impls. This is a [breaking-change] (for gated code) in that when you implement `Fn` (`FnMut`) you must also implement `FnOnce`. This commit demonstrates how to fix it. 2015-03-11 09:08:33 -05:00			`//~^ ERROR E0277`
Forbid coercing unsafe functions to closures Closes #9582 2014-01-16 14:20:59 -06:00			`}`