Provide zero-cost Optioned<char> #19
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This uses `char::from_u32_unsafe(u32::MAX)` as the none value. This is not a valid `char` value, and will never be a valid Unicode code point. Because of this, it is possible to provide a zero cost `Optioned<char>` by assigning the `Noned` value to this invalid code point. So long as `Optioned` holds its contract of not giving out the noned value, this can in no way be memory unsafe because the fake char is only used as a sentinel, and never as an actual character.
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Failure is not mine; it's #20. |
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Hey, thanks for this! Unfortunately, both my operating systems broke down recently, so I'm still in the process of setting up and cannot test this over the weekend. I hope I can get around to it next Monday. I'm sorry to let you wait, but I'd really like to test it before merging. |
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Thanks again, merged. Will publish shortly. |
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This uses
char::from_u32_unsafe(u32::MAX)as the none value. This is not a validcharvalue, and will never be a valid Unicode code point. Because of this, it is possible to provide a zero costOptioned<char>by assigning theNonedvalue to this invalid code point.So long as
Optionedholds its contract of not giving out the noned value, this can in no way be memory unsafe because the fake char is only used as a sentinel, and never as an actual character.