newRPL: all results mode?

[rprosperi]

(01-21-2016 12:59 PM)Claudio L. Wrote:  Since newRPL swapped the behavior of + and ADD, we have all operators in place for list processing. If all other commands also accept list processing, there's no technical barrier for returning a list of results during evaluation of an expression.
This means for example:

4 √ would return { -2 2 }
XROOT would also return all roots depending on the exponent.

When used within an expression, it would continue to evaluate normally as 2 (or more) different paths.

I wonder if a flag could activate this mode, or we should leave it alone and have new command names that return all roots (√ALL and XROOTALL for example).

This mode is not necessarily good for all cases, I can think of a Newton-Raphson iteration involving a square root, where each iteration would double the number of results and eat all the memory.

Any thoughts?

I think newRPL should, by default, behave the same as RPL in order to get expected results from existing code. Enhanced results, like this, are very useful for those that understand and expect them, but should IMHO only be enabled by some deliberate action, like setting a flag. I think backward compatibility for a core function such as this will be essential for adoption by many users.

New command names for the enhanced modes is nice as it certainly adds clarity, but could easily get out of control due to likely large number of variations. How many would you expect?