Re: Compiler errors and recursive nested functions

[Dylan Knutson]

DPaste has stopped responding to requests at the time of writing, 
so here's the code in case its still down by the time someone 
reads this:

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import std.algorithm : map;
import std.range : isInputRange, ElementType;

// Doesn't work
//template deepMap(alias pred, Range)
//if(isInputRange!Range)
//{
//      static if(isInputRange!(ElementType!Range))
//      {
//              alias deepMap = map!(a => deepMap!(pred, typeof(a))(a));
//      }
//      else
//      {
//              alias deepMap = map!(pred);
//      }
//}

// Neither does this, for the same reason
auto deepMap(alias pred, Range)(Range r)
if(isInputRange!Range)
{
        static if(isInputRange!(ElementType!Range))
        {
                return r.map!( a => a.deepMap!(pred)() )();
        }
        else
        {
                return r.map!(pred)();
        }
}

unittest {
        import std.stdio;

        auto a = [[1, 1], [1, 1]];
        auto b = a.deepMap!(a => a + 1)();
        writeln(b);
        //assert(b == [[2, 2], [2, 2]]);
}

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