[Tutor] How to type annotate complex dictionary containing lambdas?

[boB Stepp]

On Sun, Nov 17, 2019 at 9:26 AM Mats Wichmann <mats at wichmann.us> wrote:
>

I will get back later to the class refactoring operation, but thanks
for your example.  It will be quite helpful!

> As you your actual question...
>
> >> goal_year_params: Dict[str, Any] = {
>
> the two types that the dict's values can be per your snip is str or
> list, so start there:
>
> goal_year_params: Dict[str, Union(str, List)]

A typo in there. "Union" has to have brackets not parentheses.

I tried that and got an error:

pages_per_day.py|93 col 9 error| Dict entry 2 has incompatible type
"str": "Callable[[Any], date]"; expected "str": "Union[str,
List[Any]]"

Apparently because of the lambda outside of the list, I apparently
must annotate them as "Callable".  Before making my post on this to
Tutor, I had tried variations on this, but I must have gotten lost in
the twisted unnecessary complications of my dictionary!  ~(:>))  I
will play around some more with getting the annotations right before
addressing refactoring the dictionary mess into something reasonable.
Point of honor, ya know!

> if you want to go further you can then specify what the list consists
> of, etc.
>
> >>            "greeting_msg": "Please enter the date by which you wish to attain"
> >>            " your goal.\n",
> >>            "input_prompt": "Enter year of your goal as an integer:  ",
> >>            "date_value_err_ck": lambda goal_year: date(goal_year, 1, 1),
> >>            "err_msg": "That is not a valid year.  Please try again.",
> >>            "conditions": [
> >>                (
> >>                    lambda goal_year: goal_year < date.today().year,
> >>                    lambda goal_year: print(
> >>                        "Have you invented a time machine?  If not,
> >> please enter a"
> >>                        " year that makes more sense!"
> >>                    ),
> >>                ),
> >>                (
> >>                    lambda goal_year: goal_year >= date.today().year + 100,
> >>                    lambda goal_year: print(
> >>                        "Have you discovered the secret to eternal life?
> >>   And how"
> >>                        " long is this book anyway?  Please enter a year that"
> >>                        " makes more sense."
> >>                    ),
> >>                ),
> >>            ],
> >>        }
> >
> >
>
> _______________________________________________
> Tutor maillist  -  Tutor at python.org
> To unsubscribe or change subscription options:
> https://mail.python.org/mailman/listinfo/tutor



-- 
boB