The former wording was just a little vague and potentially
ambiguous. It's now more clear about when a true value is returned,
and when false is returned.
- /* Returns Boolean indicating whether move was legal and added. */
+ /* Returns true if move was legal and added, false otherwise. */
add_move(square) {
/* Cannot move to an occupied square. */
if (this.state.board[square])
add_move(square) {
/* Cannot move to an occupied square. */
if (this.state.board[square])