Yet Another Switch-Case Syntax Proposal

[Marko Rauhamaa]

>>>> Instead of disabling fallthrough by default, why not disable it all
>>>> together?
>>>
>>> I was tempted but there are cases in which it's useful. An example

No, it is never useful, it never was. It came into being by accident, a
design bug turned into an advertised feature.

>>> switch day casein ("Monday", "Thursday", "Wednesday", "Tuesday",
>>> "Friday"):
>>>      gotowork = True
>>>      continue
>>> casein ("Monday", "Thursday", "Wednesday", "Tuesday", "Friday"):
>>>      daytype = "ferial"
>>> casein ("Saturday", "Sunday")
>>>      daytype = "festive"

That "casein" next to "switch" bugs me. Did I already propose:

   switch: local_sabbath()
   case (1, 2, 3) as sabbath:
       ...
   case 6:
       ...
   else:
       ...

The key is to look at precedents:

   try:
        ...
   except (E1, E2) as e:
        ...
   except ...:
        ...
   finally:
        ...

and:

   lambda: expression


The "switch: day" format is a hybrid of the "try" and "lambda" syntaxes
and would be compatible with existing Python editors as well as general
Python sensibilities.


Marko