An efficient way to make hash maps with insertion ordering

Re:An efficient way to make hash maps with insertion ordering by rob74 on Thursday July 01, 2021 @11:33AM (#27700189)

Hash maps are a fairly recent addition to the standard data structures "library", because they are relatively performance-intensive. They are of course very useful and therefore commonplace now, but I think that only came about after the rise of dynamic languages which have built-in hash maps (Javascript objects, PHP "associative arrays" etc.). So nowadays any new programming language which wants to attract web developers (e.g. Go) needs a built-in hash map.

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Re:An efficient way to make hash maps with insertion ordering by boardwaalk on Thursday July 01, 2021 @03:51PM (#27703774)

Ehh, hash tables were invented in the 50s and were and are used wherever they are useful. I’m pretty sure a running joke is that every decently sized C program contains a half dozen hash table implementations. They’re not recent.

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Re:An efficient way to make hash maps with insertion ordering by mypalmike on Thursday July 01, 2021 @12:52PM (#27701234)

Hash maps have been commonly used in C since just about forever.

"isn't a insertion order hash map, basically just a list?"

No. They are different in the computational complexity of random access operations.

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Re:An efficient way to make hash maps with insertion ordering by benibela on Thursday July 01, 2021 @06:44PM (#27705806)

But the standard C++ std::unordered_map only came with C++11

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