I hate to pick on formatting, but can you please get rid of the braces here? They add a bunch of extra vertical space for no gain, and this module in general doesn't use braces with `version` blocks if they only have one line.

This _is_ one of those cases though where I really wish we had some sort of conditional operator that worked with `version` or `static if`, because then you could do something like

    formatReflectTest(f, "%e", version(MinGW) ? `3.140000e+000` : `3.140000e+00`);