From: Emil Dotchevski (emildotchevski_at_[hidden])
Date: 2019-10-22 22:42:00
On Tue, Oct 22, 2019 at 3:13 PM Robert Ramey via Boost <
boost_at_[hidden]> wrote:
> Now this particular case - providing a provable correct parser for a
> simple language - IS a toy problem.
It does not follow that the only valid reason to do it is to play games.
> Implementing a parser derived from
> a formal grammar CAN be done quite easily with boost spirit - if only
> for the the testing portion of the project. (Of course if spirit were
> used in the main product, much less testing would be required!).
>
> both Vinnies method and your method create huge amount of extra work for
> various persons involved in the process. I'm not over thinking it,
> you're not thinking big enough. It's not just use cranking up some code
> it's sucking in all the other participants to do our work for us.
>
I get your point that it's easier to reason about correctness if you can
trust the individual components. This reflects a "white box testing"
mentality. But if Spirit is bug-free, logically it does not follow that a
library that uses it has better chance of being bug-free, compared to a
library that does not. Either way, you ought to test, ignoring any and all
knowledge of its internals.
Consider also even if using tested components can get you to bug-free
implementation quicker (which isn't proven in this case), on balance it is
better if you don't depend on another library. I'd be surprised if you
think otherwise.