33 lines
1 KiB
Markdown
33 lines
1 KiB
Markdown
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Binary Literals
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===============
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There’s a relatively common request to add binary literals to C# and VB. For bitmasks (e.g. flag enums) this seems genuinely useful, but it would also be great just for educational purposes.
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Binary literals would look like this:
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``` c#
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int nineteen = 0b10011;
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```
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Syntactically and semantically they are identical to hexadecimal literals, except for using `b`/`B` instead of `x`/`X`, having only digits `0` and `1` and being interpreted in base 2 instead of 16.
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There’s little cost to implementing these, and little conceptual overhead to users of the language.
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# Syntax
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The grammar would be as follows:
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> _integer-literal:_
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>   ...
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>   _binary-integer-literal_
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>
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> _binary-integer-literal:_
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>   `0b`   _binary-digits_   _integer-type-suffixopt_
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>   `0B`   _binary-digits_   _integer-type-suffixopt_
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>
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> _binary-digits:_
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>   _binary-digit_
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>   _binary-digits_   _binary-digit_
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>
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> _binary-digit:_   one of
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>   `0` `1`
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