[Cfp-interest 1622] Re: TS3 annex review

[Fred J. Tydeman]

On Thu, 4 Jun 2020 16:31:26 -0700 Jim Thomas wrote:
>
>My understanding 
>
>A is a subset of B iff every element of A is an element of B. The C standard has several instances of "subset" with this meaning.
>
>A is a strict subset of B iff A is a subset of B and A is not equivalent to B.
>
>"Strict subset" and "proper subset" mean the same thing.  An internet search indicates that both terms are widely used and mean the same thing.

Agree with all of above.

>In the TS3 there are instances of "is a subset of (or equivalent to)". The parenthetical part isn't really needed (which is why it's in parentheses). We're trying to be extra clear that we don't mean just strict subset.
>

Annex X has for FLT_EVAL_METHOD:

"0 evaluate all operations and constants, whose semantic type comprises a set of values
    that is a strict subset of the values of float, to the range and precision of float;"

So, "float op float" is not evaluated to "float" as per that (which struck me as strange).

However, it is evaluated to "float" by the second clause:

"evaluate all other operations and constants to the range and precision of the semantic
type;"

So, perhaps removing "strict" would improve things.

---
Fred J. Tydeman        Tydeman Consulting
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