Using std.algorithm.map: Error: cannot implicitly convert expression of type MapResult!

[bearophile]

Dfr:

>     auto vtypes = map!(to!Variant[string])(lols);

The short template instantiation syntax only supports a single 
token, to avoid mistakes,so you need to add ():

map!(to!(Variant[string]))(lols);

That is better written:

lols.map!(to!(Variant[string]));

But I don't know if this is enough to fix your code.

Bye,
bearophile