Re: [Nasm-devel] git master branch disallows question mark in identifiers

[C. M. <pu...@38...>]

On at 2018-12-14 01:38 -0800, H. Peter Anvin wrote:
> On 12/4/18 4:02 AM, C. Masloch wrote:
>>
>> Oh yeah, you're right. Yes, it'd definitely be useful to support both
>> the operator and question mark in identifiers.
>>
> 
> OK, the most logical way to deal with this seems to be to treat ? as a
> *keyword*, rather than a *character*. In other words, since ? is
> legitimate in identifiers, it is also a legitimate keyword. Just like
> any other keyword, it has to be separated from other keywords by
> whitespace or other non-identifier characters.

Thanks, I tested building from git 33b5d21fbdc9 and it seems to handle everything the way it should, ie still allowing me to use the question mark in define names.

>> (Side question: Would it be possible to "evaluate" expressions with
>> strings as result? Eg << db _FAT16 ? "FAT16" : "FAT12" >>. Currently I
>> use << db "FAT1",'2'+4*!!_FAT16 >>
>> https://bitbucket.org/ecm/ldosboot/src/b469e243526d4fbdfe79d6ef4ef677ff2372eb19/boot.asm#lines-490
>> , which only uses a string that fits as a numeric constant in a byte.)
> 
> I'm afraid not, although
> 
> 	db "FAT1", _FAT16 ? '6' : '2'
> 
> ... does work.
> 
> This is because in NASM, strings used in expressions are always
> converted to numbers. This isn't something we can realistically change
> without who knows what breakage.

Yeah, figures.

> Now, since NASM does internal 64-bit arithmetic strings converted to
> numbers can be up to 8 characters long, but since there is no 5-byte
> object you can't trivially use it in the way you'd expect.
> 
> Now, if you had an 8-byte field you could indeed do:
> 
> 	dq _FAT16 ? "FAT16" : "FAT12"
> 
> ... and you'd get a 5-character string with 3 bytes of zero padding.


A side question: Your mails never seem to show up in https://sourceforge.net/p/nasm/mailman/nasm-devel/ -- what's up with that?

Regards,
ecm