//! Defines a constant for each file on the board.
pub const FILE_A: usize = 0;
pub const FILE_B: usize = 1;
pub const FILE_C: usize = 2;
pub const FILE_D: usize = 3;
pub const FILE_E: usize = 4;
pub const FILE_F: usize = 5;
pub const FILE_G: usize = 6;
pub const FILE_H: usize = 7;