[fpc-pascal] Re: Assigning pointer address

[michael.vancanneyt at wisa.be]

On Mon, 1 Oct 2012, Tomas Hajny wrote:

>>>
>>> IIUC, size PtrUint varies by architecture, which is more or less the
>>> point of PtrUint.
>>> Having this variation documented as Darius suggested above makes things
>>> much clearer, because the programmer may be working on one platform and
>>> programming for another (with {$IFDEFS}...).
>>
>> Yes and no.
>>
>> You're supposed to treat this as an opaque type, i.e. all you're supposed
>> to know is that it is:
>> 1) An integer type (signed or not).
>> 2) Same size as a pointer type on all platforms.
>>
>> If we start specifying when it is of what type, then
>> a) we need to maintain this.
>> b) people will start making assumptions.
>>
>> We exactly need to avoid b)
>
> You're obviously right, but since we include documentation built on a
> 32-bit architecture as a universal one for all releases/architectures and
> since it currently explicitly includes information that 'PtrUInt = DWord',
> we should either make sure that this equation doesn't appear in the
> documentation (which may be difficult considering how the docs are
> created), or (more likely) provide additional information which allows the
> reader to interpret the statement correctly. Choosing the right wording
> (to stress the opaque nature of this type) is obviously up to you, but a
> request for some kind of clarification added to the docs is IMHO
> absolutely reasonable.

Absolutely, and I plan to do so :-)

Michael.