Maude-help mailing list

[Steven Eker <eker AT csl.sri.com>]

Hi Phil,

I think rule based programming and term rewriting have gone out of fashion in 
recent years - witness the demise of RULE and the folding of RTA into a more 
general formal methods conference. Satisfiablility, in particularly SMT seems 
to be where the action is these days, as far as practical formal methods 
tools.

Rival systems to Maude have traditionally been:

ASF+SDF - no longer actively developed, successor is Rascal
Stratego - created by a former ASF+SDF developer
ELAN - no longer actively developed,
Tom - created by a former ELAN developer
CafeOBJ - still under active development

Maude is still being actively developed; we expect to put out a new public 
version this year. New features that are already working in the development 
version include rewriting modulo SMT and partial support for unification 
modulo 
associativity (it's an infinitary theory so support will likely always be 
partial).

As far as your code goes, I've only quickly eye-balled it without 
understanding what it is doing; I notice a couple of things:

(1) Using conditional equations to check for degenerate data (L =/= []) is 
expensive. The preferred technique is to put non-degenerate data in subsorts 
(non-zero integer, non-empty list etc) and then give the variable the 
appropriate subsort.

(2) Rules are (at least) an order of magnitude more expensive than equations, 
so only use them when you need the possibility of alternative rewrites 
(search, fair rewriting).

Steven

On Tuesday, April 26, 2016 06:34:14 PM Phillip Schanely wrote:
> Hello all!  I am just starting to play around with Maude, and have
> been attempting to do some software optimization work in it.  Looks
> like this mailing list is stagnating a bit - is there something more
> active and/or modern that people prefer over Maude? (it looks pretty
> darn neat to me)
> 
> Essentially, I am trying to to optimizations over standard higher
> order functions.  A description of that process is here:
> 
> https://medium.com/@pschanely/e5153ab69753
> 
> I am hoping someone who cares about such things might have suggestions
> for papers I should read and/or people I should talk to.
> Additionally, I've got some initial Maude code is here:
> 
> https://github.com/pschanely/wf-optimizer/blob/master/demo.maude
> 
> If (and only if!) it happens that someone on this list is interested
> in this topic, I'd also really appreciate a code review from someone
> who actually knows what they are doing in Maude.
> 
> And, also, thanks guys.  This is an amazing system.
> 
>   Phil