Ex 5 Level 6 flatmap

[brookie13]

Hi currently stuck with level 6 for exercise 5. I am not too sure on how I can return a Maybe without having to typecast it. I've thought about using the map() function in the class and then take the Maybe value inside but I realised that the value would be considered as R instead of Maybe (thus leading to typecasting which brings up the warning). What is another way to go about with this problem?

[bransometan]

I managed to solve it with this approach by first assigning mapper.apply(this.thing) to the output of the Function which is Maybe<? extends R> and call it (e.g temp). Then, I just return Maybe.<R>of(temp.thing).

[glendon29]

what i did was to do mapper.apply(this.thing).orElse(null) since the orElse method u created points to this which in this case refers to the mapper.apply

[brookie13]

I attempted this method but I got the error CAP#1 cannot be converted to Maybe<? extends R>. What did you do to avoid this?

[glendon29]

@brookie13 do u mind if u share ur method

[brookie13]

@glendon29

[glendon29]

oo ur parameter is wrong. if u see the test case u realise flatMap can take in a param of Maybe

Therefore ur flatMap param must be
Function<? super T, ? extends Maybe<? extends R>>

@brookie13

[brookie13]

OHHH okay I fixed it and now it works. Thank you so much