Member functions

Question

I have a class for which I implement ranges. I would like to implement functions the way the phobos library does, i.e. Outside the main class.

void popBack(T)(ref T[] a) if (!is(Unqual!T == char) && !is(Unqual!T == wchar))
{
    assert(a.length);
    a = a[0 .. $ - 1];
}

Here is my version:

void popFront(T)(ref PersistentList!(T) a)
{
    a = a.next();   
}

When I try to compile this code with a letter, I get:

Error   1   Error: no property 'popFront' for type 'stmd.PersistentList!(int).PersistentList'   main.d  

I could move the member code to the main class, but since I am changing the "ref" value of the input, I cannot use popFront () I really need popFront (ref a).

What am I doing wrong?

Answer 1

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Answer 2

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int func(int[] arr)
{
    return arr[0];
}

auto arr = [1, 2, 3];
auto val = arr.func();

auto val = func(arr);

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