Single Comment

Reinhard:
It is of course OK to design X-FEN with a limited scope. But that makes it
unsuitable for applications tht require a wide scope, such as WinBoard (or
Game Courier). And when X-FEN includes features that are incompatible with
the needs for the variants in the wider scope, it makes it unacceptable for
use even for the variants it was designed for in that scope.

Fergus:
Is the FEN format you use in Game Courier described somewhere? IMO a FEN
is a device for describing game state, not for identifying the variant, so
that the variant cannot be deduced from the FEN is not really a problem. I
never thought about hexagonal boards and such, but now that I do the
logical way to implement those would be to use another charater than '/'
for separating the ranks of the FEN. E.g. '\' could mean 'start a new
rank, offsetted half a cell left w.r.t. the rank it terminates'.