[Python-ideas] Changing optimisation level from a script

[Nick Coghlan]

On 13 September 2016 at 17:34, Damien George <damien.p.george at gmail.com> wrote:
> Suggestions for setting the opt level were:
>
> 1) sys.set_default_optimize(level), with the existing
> sys.flags.optimize attribute as the accessor.
>
> 2) sys.opt_level, being a read/write attribute
>
> 3) sys._setflag(name, value) as implemented by eGenix PyRun
>
> I think option 1 is the most consistent with the existing sys module,
> although the name is rather long and I think sys.set_optimize(level)
> would be better (after all, none of the other sys.set functions have
> the word default in them).

For CPython, where we have quite a few different runtime settings,
something like the general purpose eGenix interface probably makes
more sense, for the same reason we added sys.flags in the first place:
reducing the level of API sprawl in the sys module.

> As a second preference I like micropython.opt_level([value]), which
> can set and get the value, and keeps it specific to uPy.

And if you went that way, any future general purpose "runtime flag
manipulation" API could just provide a then wrapper around that for
the optimisation flag, while still exposing this API for use from
MicroPython-specific boostrapping files.

Given those two points, I think "micropython.opt_level([value])" would
be the right way to go, with the official stance for CPython being
that configuration is an environmental problem, but some environments
(like PyRun and MicroPython) will expose a Python API rather than
using an external mechanism.

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia