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How do I generate an array in D?


I have this c++11 code:

auto gen = []() -> double { /* do stuff */ };
std::generate(myArray.begin(), myArray.end(), gen);

How would I do the same with D's array? std.algorithm.fill doesn't take a function object, and I don't know how to pass a function to recurrence.


Solution

  • Here's a version that seems to work:

    import std.algorithm, std.array, std.range, std.stdio;
    
    void main() {
      writefln("%s", __VERSION__);
      int i;
      auto dg = delegate float(int) { return i++; };
      float[] res = array(map!dg(iota(0, 10)));
      float[] res2 = new float[10];
      fill(res2, map!dg(iota(0, res2.length)));
      writefln("meep");
      writefln("%s", res);
      writefln("%s", res2);
    }
    

    [edit] Added fill-based version (res2).

    I tested it in Ideone (http://www.ideone.com/DFK5A) but it crashes .. a friend with a current version of DMD says it works though, so I assume Ideone's DMD is just outdated by about ten to twenty versions.