[Question][Hw1-1] Q1. About exception raising

[sjoon2455]

Hi, do I have to implement something like try...except... for this problem?

I am not quite sure what does it mean by "The function will raise ... when the arguments are invalid".

Could you please clarify this?

Thanks in advance.

[hyunsukimsokcho]

By saying try .. except .., I assume you are referring to exception handling in python. However, in the homework, one does not have to handle any exception, but simply throwing the exception is enough. If you are familiar with python, raise is the one throwing the exception. One may search about how exception is defined and how can it be thrown in OCaml.

[sjoon2455]

@hyunsukimsokcho, thanks for answering.

I guess raise exception Invalid_argument is what I need at this point.
However, if I run the implemented function with invalid arguments, for instance sigma "1" 10 or sigma 1.1 10, it does not throw Invalid_argument error. Could you guide me a bit more?

Thanks.

[hyunsukimsokcho]

(I assume you are referring to problem 1) Those two cases you mentioned will raise type error even before executing your code. Since OCaml is strongly-typed language, two arguments for sigma should be int. However, even if one passes correctly typed arguments, there are cases where usual sigma cannot be computed properly. For those cases, throw exception.

[hyunsukimsokcho]

minor correction: sigma "1" 10 and sigma 1.1 10 will execute your code however, they will throw type error when trying to evaluate + in proper implementation of sigma. Note that + in OCaml only works with two arguments of which type is int.

[sjoon2455]

@hyunsukimsokcho, I understood your point! Thank you. Issue resolved, so closing this issue.