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True Myth / maybe / orElse

Function: orElse()

Call Signature

orElse<T, R>(elseFn, maybe): Maybe<ValueFor<R>>

Like or, but using a function to construct the alternative Maybe.

Sometimes you need to perform an operation using other data in the environment to construct the fallback value. In these situations, you can pass a function (which may be a closure) as the elseFn to generate the fallback Maybe<T>.

Useful for transforming empty scenarios based on values in context.

Type Parameters

T

T

The type of the wrapped value.

R

R extends AnyMaybe

Parameters

elseFn

() => R

The function to apply if maybe is Nothing

maybe

Maybe<T>

The maybe to use if it is Just.

Returns

Maybe<ValueFor<R>>

The maybe if it is Just, or the Maybe returned by elseFn if the maybe is Nothing.

Call Signature

orElse<T, R>(elseFn): (maybe) => Maybe<ValueFor<R>>

Like or, but using a function to construct the alternative Maybe.

Sometimes you need to perform an operation using other data in the environment to construct the fallback value. In these situations, you can pass a function (which may be a closure) as the elseFn to generate the fallback Maybe<T>.

Useful for transforming empty scenarios based on values in context.

Type Parameters

T

T

The type of the wrapped value.

R

R extends AnyMaybe

Parameters

elseFn

() => R

The function to apply if maybe is Nothing

Returns

The maybe if it is Just, or the Maybe returned by elseFn if the maybe is Nothing.

(maybe): Maybe<ValueFor<R>>

Parameters

maybe

Maybe<T>

Returns

Maybe<ValueFor<R>>