[Tutor] A beginner having problems with inheritance

[Sydney Shall]

On 09/07/2014 20:17, Danny Yoo wrote:
>> My error was simply that I inadvertently used the same name for a method
>> (function) in the derived class that I had already used in the parent class.
>> The result was then a very obscure error because the wrong calculation was
>> performed and later on an array was empty.
>> Fortunately, thanks to you very generous tutors I have learned to read the
>> error trace very carefully indeed.
>
> Ah, yes, that one.  It's happened to me too.
>
> It's one of the reasons why inheritance makes me nervous sometimes.
> It's a problem that's fairly language-independent.
>
> (If you'd like to know the details, the example that I was involved in
> is described in the comments on:
> https://github.com/bootstrapworld/js-numbers/pull/5.  Essentially, we
> subclassed some base class, and wrote a method called BigNumber.exp()
> to do exponentiation.  Unfortunately, we didn't realize that our
> superclass already had defined an exp() method.  It ended up showing
> up as a very strange, obscure error.  Same class of problem.)
>
>
> Side note, Python does have a hack called "name mangling" that can be
> used to try to avoid this problem:
>
>      https://docs.python.org/2/tutorial/classes.html#private-variables-and-class-local-references
>
>
> Good luck!
>
Thanks for the reply.
I had read the second reference that you gave some time ago, but of 
course I had forgotten about it.
I shall try and make use of it now.
Thanks for the help.

-- 
Sydney Shall
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