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Re: Comparison operators

From: Bo Persson <bo_at_[hidden]>
Date: Mon, 19 Dec 2022 16:05:06 +0100
On 2022-12-19 at 15:32, Vladimir Grigoriev via Std-Discussion wrote:
> There is another unclear phrase in the C++ 20 Standard relative to
> comparison operators.
> «3 The return value V of a defaulted == operator function with
> parameters x and y is determined by comparing corresponding elements xi
> and yi in the expanded lists of subobjects for x and y (in increasing
> index order) until the first index i where xi == yi yields a result
> value which, when contextually converted to bool, yields false. If no
> such index exists, V is true. Otherwise, V is false.»
> What does the last statement « Otherwise, V is false.»» mean?

It is the else-part of the preceding 'if', just to make sure.

When you only have "If no such index exists, V is true.", you might
possibly wonder if V can be true anyway? So the next statement
clarifies(?) that if it is not true, it must be false.

Received on 2022-12-19 15:05:13