> to anyone with a 5th-gen language on their resume: how's a hash table implemented? use of a feature or function without understanding why and how it works can

> to anyone with a 5th-gen language on their resume: how's a hash table implemented? use of a feature or function without understanding why and how it works can lead to really interesting performance problems, even if the code is functionally correct) Someone recently argued something similar with me, although they were even more emphatic about the importance of taking an interest in how the datastructures you're using are put together. Interestingly though, there are a few well known languages where if you assumed that the default Map was implemented as a Hashtable, you'd be making bad assumptions, as it's a Hash Array Mapped Trie, a data structure that certainly wasn't taught back when I was studying computer science. Unsurprisingly, despite the strong opinion that you should always find out how the things you use are implemented, my interlocutor didn't know this. And I didn't expect him to. I think that an obsession with particular shibboleths that "any decent programmer should know" misses the point that you're a decent programmer because of what you can do when you need to, not because of the datastructure implementations you've memorised.