The `std` feature is not discoverable (was: `FromBitsError` doesn't implement `Error`)

[drewcassidy]

enumflags2 uses FromBitsError for the error for TryFrom, but the struct doesnt implement std::error::Error which makes it unwieldy to use, for example with the ? operator or a diagnostics package like Miette

45 | pub struct FromBitsError<T: BitFlag> {
 | ------------------------------------ doesn't satisfy `_: Error`
 |
 = note: the following trait bounds were not satisfied:
 `FromBitsError<DDSPixelFormatFlags>: std::error::Error`
 which is required by `Result<BitFlags<DDSPixelFormatFlags, u32>, FromBitsError<DDSPixelFormatFlags>>: IntoDiagnostic<BitFlags<DDSPixelFormatFlags, u32>, FromBitsError<DDSPixelFormatFlags>>`

[meithecatte]

You need to enable the std feature on enumflags2. Though, good point, this is not entirely discoverable, and perhaps the feature should be enabled by default.

[meithecatte]

Marking this as breaking change, as enabling the std feature by default would require action from everyone who's using the library on #![no_std]

[drewcassidy]

Makes sense. I think it really just needs a more helpful error message but that's more a complaint for the rust compiler team