Data.Result

Operations over Result.

The type is wired in; the prelude opens this module, so these are in unqualified scope everywhere.

Functions and Values

is_ok : forall a b. (Result(a, b)) -> Bool

True when the result is Ok.

is_err : forall a b. (Result(a, b)) -> Bool

True when the result is Err.

map_result : forall e0 a b c. ((c) -> b ! {e0}, Result(c, a)) -> Result(b, a) ! {e0}

Apply f to the Ok value, leaving an Err untouched.

and_then_result : forall e0 a b c. ((a) -> Result(b, c) ! {e0}, Result(a, c)) -> Result(b, c) ! {e0}

Chain a result-returning function, short-circuiting on Err (monadic bind for Result).

result_or : forall a b. (a, Result(a, b)) -> a

The Ok value, or the default d when the result is Err.

ok_of_option : forall a b. (a, Option(b)) -> Result(b, a)

Convert an Option to a Result, using err in place of None.

option_of_result : forall a b. (Result(a, b)) -> Option(a)

Convert a Result to an Option, discarding the error.