This is a complicated function that walks the expression tree and tries to simplify it. Since sometimes a simplification made at some level of the expression tree can lead to a simplification at a higher level of the expression tree, we need to walk the expression tree from the bottom up.
# S3 method for edist
simplify(x, ...)The edist object to simplify
Additional arguments to pass (not used)
The simplified object
Also, since some simplifications can lead to a change in the class of the distribution, we need to be careful to update the class of the distribution as we simplify it.
Finally, the simplifications we initially choose to do can
prevent us from doing other simplifications that may ultimately
be more beneficial. So, we need to try all valid simplifications,
creating new edist objects for each simplification, and then
choose the one that is the most simplified.