Re: ranges reading garbage

[anonymous via Digitalmars-d-learn]

On Sunday, 15 February 2015 at 18:13:44 UTC, John Colvin wrote:

Simplified from something bigger:

import std.range, std.algorithm, std.stdio;

void foo(float[] data, float[] xs, float[] ys)
{
    auto indices = iota(0, data.length, ys.length)
        .map!(xBase =>
                iota(xBase, xBase + ys.length - 1)
                .map!(y =>
                    only(y, y+ys.length, y+ys.length+1, y+1))
                .joiner())
        .joiner();
    writeln(indices);
}

void main()
{
    foo([1,2,3,4,5,6,7,8],
            [0.1,0.2], [10,20,30,40]);
}

prints things like [0, 4, 5, 1, 1, 1459971595, 1459971596, 2, 2, 1459971596, 1459971597, 3, 4, 8, 9, 5, 5, 4441427819, 4441427820, 6, 6, 4441427820, 4441427821, 7] but the output isn't consistent, the big numbers change on each run.

Reduced some more:

import std.algorithm, std.stdio;
void main()
{
    int ys_length = 4;
    auto indices = [0]
        .map!(xBase => [0].map!(y => ys_length))
        .joiner();
    writeln(indices);
}