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From: Kaz Kylheku <330-706-9395@kylheku.com>
Newsgroups: comp.programming
Subject: Re: Designing a suite of algorithms in C++
Date: Mon, 1 Feb 2016 23:24:53 +0000 (UTC)
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On 2016-02-01, Paul <pepstein5@gmail.com> wrote:
> class Algorithm{ 
>
> public: 
> Algorithm(some parameters); 
> virtual void findSolution() = 0; 
> virtual ~Algorithm()
> {}
> }; 

This interface only supports algorithms that either find a solution, for
any combination of parameters, or else do not terminate.

Your findSolution function has no way to indicate "I have stopped
searching, and found no solution".

If the function returns, since it has no return value, and the
interface has no useful member functions to inspect any state,
we can assume that the solution was found. So if the solution cannot
be found, the function doesn't return, right?

Not to mention that, quite often, when algorithms find a solution,
we want to know *what* that solution is, not only *that* it exists.