*“the count() member function sounds like it should be non-modifying, but in fac... | Hacker News

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		Someone on May 28, 2020 \| parent \| context \| favorite \| on: The use of `class` for things that should be simpl... “the count() member function sounds like it should be non-modifying, but in fact it needs to update member data and thus cannot be const” That isn’t correct. Just declare count as mutable. See https://en.cppreference.com/w/cpp/language/cv. Memoization is a valid use case for that feature.

ketzu on May 28, 2020 [–]

Often it's the motivating example when the feature gets explained.

hhmc on May 28, 2020 | [–]

I would argue that mutexs or other concurrency primitives are the quintessential example, but caching is the other big one.

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