[Om3] Language Dictionaries (Was: Re: Initializing OM3 at 2013 Process)

[Lars Hellström]

David Carlisle skrev 2014-05-05 12.40:
> On 05/05/2014 10:28, Lars Hellström wrote:
>
>> 1. More IEEE float formats.
>>
>> OM currently only supports the 64-bit double format for floats, but
>> the current version of the source IEEE standard defines floats of
>> arbitrarily high precision (every multiple of 32 bits, if I recall
>> correctly; there's a formula for how many bits go into the exponent
>> and how many go into the mantissa). The OM standard could be extended
>> to allow OMF with hex attribute values any multiple of 8 hexdigits
>> long. (https://trac.mathweb.org/OM3/ticket/137)
>>
>> A natural translation of some
>>
>> <OMF hex="0123456789ABCDEF0123456789ABCDEF"/>
>>
>> (128 bits) to strict OM2 would be as some
>>
>> <OMA> <OMS cd="IEEEfloat" name="fromOMB"/>
>> <OMB>ASNFZ4mrze8BI0VniavN7w==</OMB> </OMA>
>
> I much prefer the existing OMS notation for that. There always were
> different formats for floating point numbers so could have used a CD for
> all of them, OMF special cased Double as a convenience as that was (and
> is) overwhelmingly the most common type for floating point literals
> in programming languages. I don't think the extended precision types
> change that reasoning any more than IEEE single. This is a cosmetic
> change that breaks applications unless they are updated or the code is
> pre-processed back to OM2.

A quite reasonable position. But then the standard should explicitly state 
that OMF is provided as a convenience, and suggest the constructor symbol 
solution for people who want other types of floats.

>> 2. OMOBJs as mathematical objects
>
> I thought we had a meta CD for that, but apparently not (or at least we
> don't seem to have one now?) meta CD allows the quoting of CDs (only)

Yes, and I would argue that without a quoting mechanism, the meta CD gets it 
wrong (embedding naked omels for the OMOBJs in the .ocd file, rather than 
quoted omels).

Lars Hellström

> I'm sure at one time we had a CD with symbols OMOBJ OMA etc.
>
> David
>
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