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Re: Motion P1788/M0044:Constructors -- Voting Period begins



The motion seems to be no more than changing the cross reference to the new location.
I vote  YES.

However, I would prefer that 1788 remove entirely text2interval... given that such issues as decimal-to-binary conversion, parsing and evaluation of exact arithmetic quotients, values for pi (etc), are either routine parts of programming languages, or in their libraries.

And to cap it off, this complicated and unnecessary part is (at least in the current motion) OPTIONAL.

My view is that the host programming language must be adequate to create any literal number which is the inf or sup value stored in a bare interval, and to create from any bare interval the two numbers which are its inf and sup values (including infinity, NaN). If this is the case, there is no need for text2interval. If this is NOT the case, the language is essentially unsuitable for interval arithmetic. (A clever enough person could still build interval arithmetic out of character strings or some other hacks, but I would call this evidence of
unsuitability...)

Furthermore, text2interval violates what would seem to be a fundamental rule of "good hygiene". That is it admits of notation like 0.1 which is close, but not the same, in meaning as 0.1 in the programming
language.

Richard Fateman