subst(lambda ...), was: multiple evaluations & integrate



On 2013-06-09, Stavros Macrakis <macrakis at alum.mit.edu> wrote:

> No function in Maxima should substitute variable or function values, or
> apply functions, unless that is its principal and explicit definition (e.g.
> "apply"). So the integrate example is certainly a bug.(*)

> (*) This also suggests that subst(lambda([x]...),...) should *not* in
> principle perform the lambda application.

Agreed.

> Not sure whether "but it's so handy" is a good enough excuse....

Well, it appears that it's not widely used, and the only instances that
I found (in nusum) are probably easily fixed up. Given that, are you in
favor of changing subst(lambda([x]...),...) to not evaluate lambda
expressions? (As I mentioned before, the change is actually needed in
SIMPLIFYA.)

best

Robert Dodier