cplusplus / cplusplus/draft

[basic.fundamental] p12 Saying that "range of representable values" is implementation-defined is helpful

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Description

[basic.fundamental] p12 says

The value representation of floating-point types is implementation-defined.

For other integer types, we did not emphasize this point for them. Isn't the value representation for integer types also implementation-defined? Consider the impact for the value representation with the difference between big-endian and little-endian in a concrete environment, and assume the width for short int is always16.

short i = 2;
//  big-endian 00000000 00000010
// little-endian 00000010 00000000

The example wants to convey that saying the value representation is implementation-defined does not mean the range of representable values is implementation-defined too.

So, saying that the value representation of floating-point types is implementation-defined is not all that important here. It is not helpful for interpreting whether a floating-pointer type can represent positive infinity or not. As said in https://github.com/cplusplus/draft/issues/5407#issuecomment-1107394398, we consider the existence of these values for a floating-pointer type is implementation-defined, which means that we care more about the range of representable values. I think, change the above rule to that

The range of representable values for floating-pointer types is implementation-defined.

which is more helpful.

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Research direction

Locate [basic.fundamental] paragraph 12 in the TeX draft source and read the surrounding rules on integer and floating-point representations. Compare the current wording with the issue's proposed wording and the linked discussion in issue 5407. Done means the wording accurately communicates the intended implementation-defined property and the corresponding draft change is reviewed.

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Assessment

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tex
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documentation
Issue type
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Newbie friendliness
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