[Haskell-cafe] Quickcheck research

[Jacques Carette]

On 11-11-23 08:28 PM, Jason Dagit wrote:
> On a similar line of reasoning, I've wondered if Perlin style noise
> generation could be applied to get a sort of "fuzzing" effect.  This
> would be more interesting for cases where writing instances of
> arbitrary is hard to do but test cases do exist.  Apply some sort of
> pseudo-random noise to your examples and see if your properties still
> hold.  I could see this having applications in parsers.
>
> As far as I can tell, no one has used Perlin noise on algebraic
> structures.  It seems to have only been applied to real valued spaces.
>   Imagine having a parse tree then applying noise to the structure of
> the tree then "unparsing" the tree back to concrete syntax.  You're
> making the structure noisy instead of just fussing the concrete syntax
> directly (which should increase the frequency that you change the
> shape/meaning instead of just changing the tokens in the parse tree).
>

Interesting idea!  With the "strategy based" unified 
Quickcheck/Smallcheck that we're finishing up, it would be quite easy to 
program that as a new generation strategy and try it.

We've already got Boltzmann sampling on the list of things to look at in 
the future.

Jacques