[GiNaC-devel] printing of class power

[Vladimir V. Kisil]

	Dear Richard,

	Your proposal seems to be sensible to me. As a variation of it:
  can "print_deterministic" be just a flag for any declared printing
  method? It may be not so useful in outputs for C or Python, but
  printing a tree in a deterministic way may be an advantage. 

	Best wishes,
	Vladimir
-- 
Vladimir V. Kisil                  http://v-v-kisil.scienceontheweb.net
  Book:      Geometry of Mobius Maps       https://doi.org/10.1142/p835
  Soft:      Geometry of cycles         http://moebinv.sourceforge.net/
  Jupyter notebooks:        https://github.com/vvkisil?tab=repositories

>>>>> On Tue, 7 Jan 2025 23:20:04 +0100, "Richard B. Kreckel" <kreckel at in.terlu.de> said:

    RK>  Hi,
    RK> This is now about more than class 'power'...

    RK> On 1/7/25 12:12 AM, Stefan Weinzierl wrote:
    >> replacing print_func<print_dflt>(&power::do_print_dflt) by
    >> print_func<print_context>(&power::do_print) makes sense to me, it
    >> will treat the class power in the same way as the classes add and
    >> mul.

    RK> Even if we fix it this way, the question remains: What purpose
    RK> does the base class 'print_context' serve other than being an
    RK> alias for 'print_dflt' - at least for classes 'add', 'mul',
    RK> 'power', 'numeric', 'symbol', 'pseries', 'lst', 'matrix'?
    RK> (There's still the same problem for 'clifford', 'spinmetric' and
    RK> friends that could be fixed as well.)

    RK> I propose this: 1) Let's modify it such that 'print_context'
    RK> provides the output of 'print_dflt' for all classes derived from
    RK> 'basic'.  2) Let's add a 'print_deterministic' subclass which
    RK> lexicographically sorts the elements of classes where output
    RK> order normally depends on addresses. Document it with a clear
    RK> warning that the traversal-order might differ from the output
    RK> order for this print context type.

    RK> Comments? (Notably about the first point, in case there is
    RK> insight about the reasons of having two types 'print_context'
    RK> and 'print_dflt'.)

    RK> All my best, -richy.  -- Richard B. Kreckel
    RK> <https://in.terlu.de/~kreckel/>