on writing a while loop for rolling two dice

[Chris Angelico]

On Mon, Aug 30, 2021 at 9:53 AM dn via Python-list
<python-list at python.org> wrote:
>
> On 29/08/2021 22.24, Chris Angelico wrote:
> > On Sun, Aug 29, 2021 at 8:14 PM dn via Python-list
> > <python-list at python.org> wrote:
> >> Efficiency:
> >> - wonder how max( d ) == min( d ) compares for speed with the set() type
> >> constructor?
> >
> > That may or may not be an improvement.
> >
> >> - alternately len( d ) < 2?
> >> - or len( d ) - 1 coerced to a boolean by the if?
> >
> > Neither of these will make any notable improvement. The work is done
> > in constructing the set, and then you're taking the length. How you do
> > the comparison afterwards is irrelevant.
>
> It was far too late for either of us (certainly this little boy) to be
> out-and-coding - plus an excellent illustration of why short-names are a
> false-economy which can quickly (and easily) lead to "technical debt"!
>
>
> The "d" is a tuple (the 'next' returned from the zip-output object)
> consisting of a number of die-throw results). Thus, can toss that into
> len() without (any overhead of) conversion to a set.

Oh. Well, taking the length of the tuple is fast... but useless. The
point was to find out if everything in it was unique :)

Conversion to set tests this because the length of the set is the
number of unique elements; checking max and min works because two
scans will tell you if they're all the same; using all with a
generator stops early if you find a difference, but requires
back-and-forth calls into Python code; there are various options, and
the choice probably won't make a material performance difference
anyway :)

ChrisA