let performAction arr player = function
    | -2 -> try (replace arr; false) with Invalid_argument _ -> failwith "replace failed"
    | j -> try (let i = add arr player j in check arr i j player;) with Invalid_argument _ -> failwith "add/check failed"

99 |     | (j:int) -> try (let i = add arr player j in check arr i j player;) with Invalid_argument _ -> failwith "add/check failed"
           ^^^^^^^
Error: This pattern matches values of type int
       but a pattern was expected which matches values of type exn