An immutable sorted vector#4482
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We often need to deterministically iterate over some `const` collection. In some cases, we could use a `std::vector` and sort it, and do so at the time of creating the collection. In API signatures, `std::vector` doesn't capture this bit of information - i.e. that the producer took steps to guarantee determinism (see next para); or that the consumer intends to iterate deterministically. `SortedVector` does. `SortedVector` is not formally guaranteeing this property; it relies on the user defining a meaningful comparer. It's easy, though, to make sure the production of these things is done correctly (i.e. it's easy to spot a SortedVector returned with naked pointers, sorted naturally rather than a custom comparer, for example) The design is slightly more complicated than aliasing std::vector, to also block vector mutation APIs. Contents could still be mutated, but traversal order wouldn't change. PiperOrigin-RevId: 938810558
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An immutable sorted vector
We often need to deterministically iterate over some
constcollection. In some cases, we could use astd::vectorand sort it, and do so at the time of creating the collection. In API signatures,std::vectordoesn't capture this bit of information - i.e. that the producer took steps to guarantee determinism (see next para); or that the consumer intends to iterate deterministically.SortedVectordoes.SortedVectoris not formally guaranteeing this property; it relies on the user defining a meaningful comparer. It's easy, though, to make sure the production of these things is done correctly (i.e. it's easy to spot a SortedVector returned with naked pointers, sorted naturally rather than a custom comparer, for example)The design is slightly more complicated than aliasing std::vector, to also block vector mutation APIs. Contents could still be mutated, but traversal order wouldn't change.