[Newbies] closed and open interval
bert at freudenbergs.de
Mon Nov 24 17:46:43 UTC 2008
On 24.11.2008, at 18:36, Randal L. Schwartz wrote:
>>>>>> "Bert" == Bert Freudenberg <bert at freudenbergs.de> writes:
> Bert> On 24.11.2008, at 17:46, Randal L. Schwartz wrote:
>>>>>>>> "Filip" == Filip Malczak <filet00 at gmail.com> writes:
> Filip> You can always make subclass of Interval for example
>>> , add
> Filip> two variables: left and right.Make new methods:
> OpenedInterval> from: aNumber to: aNumber left: aBoolean
> OpenedInterval> from: aNumber to: aNumber right: aBoolean
> OpenedInterval> from: aNumber to: aNumber left: aBoolean right:
>>> You're exposing implementation there.
> Bert> How so?
> You're requiring the user to do their own encoding of "open = true,
> closed =
> false", when that's really no business of the user.
It might be a bad interface, but it does not expose the implementation.
> And what if you decide later to encode the four combinations as a
> single pluggable block or symbol?
Then you change the method that takes the booleans to create a block
- Bert -
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