For instance some constants I used:
const ulong NOT_EP_NOT_CUR_PLAYER = NOT_EP & NOT_CUR_PLAYER;
const ulong NOT_EP_BLACK_CASTLING_NOT_CUR_PLAYER_NOT_FIFTY_MOVES = NOT_EP_BLACK_CASTLING_NOT_CUR_PLAYER & NOT_FIFTY_MOVES;
const ulong NOT_EP_NOT_BLACK_CASTLING_NOT_CUR_PLAYER_NOT_FIFTY_MOVES = NOT_EP & NOT_BLACK_CASTLING & NOT_CUR_PLAYER & NOT_FIFTY_MOVES;
Just handy for readability.