Hi!

Just read Andrei Alexandrescu's new book, and I'm starting to experiment with using D in my algorithms research. Loved the book, and I'm loving the language so far :D

I just hit a snag, though ... I was doing something simple, for which my prototype code (in Python) was

  d, u = max((D(u,v), v) for v in V)

I first started writing it explicitly with loops, but it got a bit too verbose for my taste. Thought I'd use map and reduce, perhaps (although I'm still not sure if that's practical, as I'm reducing with max, but I'd like the argmax as well...).

Anyway -- while using attempting to use map, I suddenly got a segfault. As I hadn't really done any crazy stuff with pointers, or circumvented the bounds checks or the like, I was a bit surprised. I have now boiled things down to the following little program:

import std.algorithm;
void f() {
    auto x = 0;
    double g(int z) { // Alt. 1: return int
        auto y = x;   // Alt. 2: remove this
        return 0;
    }
    auto seq = [1, 2, 3];
    auto res = map!(g)(seq);
}
void main() {
    f();
}

When I compile and run this (dmd 2.051, OS X 10.5.8), I get a segmentation fault.

Oddly enough, if I *either* change the return type to int *or* remove the "y = x" line, things work just fine.

Am I correct in assuming this is a bug?

--
Magnus Lie Hetland
http://hetland.org


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