In my experience, the OCaml code doing recursive call and pattern
matching is a relatively bad way to reason about such rewrite systems.
Your questions are extremely pertinent, and relatively difficult to
answer in general.
For a start, I think your code indeed repeats useless traversals. This
On Sun, Oct 2, 2011 at 1:51 PM, Diego Olivier Fernandez Pons
dofp.oc...@gmail.com wrote:
OCaml list,
It's easy to encapsulate a couple of arithmetic simplifications into a
function that applies them bottom up to an expression represented as a tree
let rec simplify = function
| Plus
I forgot to mention that you need lablgtk2's adrien/mix branch for the
examples (and only for the examples iirc).
There are two reasons. It uses some additional API, especially
#as_something methods and notify::foo signals. lablwebkit also
requires a bug fix that it not merged into master yet.
On Sun, Oct 2, 2011 at 10:08 AM, Gabriel Scherer wrote:
One approach I like for such simplifications is the normalization by
evaluation approach.
NBE is neat, but I'm skeptical that it will work out of the box here:
if you apply NBE to a standard evaluator for arithmetic expressions,
it's not
Below is a quick tentative implementation of NbE, on a slightly
restricted expression type (I removed the not-so-interesting Minus
nodes).
Sorry, I forgot to give a small example of what the implementation
does. Really the obvious thing, but it may not be so obvious just
looking at the code.
