Re: What do you assume when you see fromListN in a library?

My personal expectations may be different based on what the container in question is. Elsewhere in the discussion types in `primitive` and `vector` were mentioned. They are however different. Compare to C++ code snippets, which are all morally `fromList(N)`:     std::array variantA;     for (int i = 0; i < 100; i++) {        primitive[i] = f(i);     }     // not good     std::vector<int> variantB;     for (int i = 0; i < 100; i++) {        primitive.push_back(f(i));     }     std::vector<int> variantC;     variantC.reserve(100);     for (int i = 0; i < 100; i++) {        primitive.push_back(f(i));     } I'm not a fan of changing `fromListN` to be partial function, but if that change is carried on in `vector` there should be a variant which allows to `reserve` without worrying about partiality. - Oleg On 28.2.2020 4.53, Carter Schonwald wrote:

Hey everyone:  When you see fromListN as a function in a library, do you assume / presume it’s expecting an exactly N element list ? Or do you expect/tolerate other behavior ? 

Should it reject shorter lists?

Should it truncate or reject longer lists? 

A corner case of this came up in some bug discussion I was having regarding vector,  and I shall claim and or presume that most folks assume exact size with prompt rejection of too long or too short. 

Thoughts please ?

-Carter 

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