[Python-ideas] except expression

[David Mertz]

On Thu, Feb 13, 2014 at 3:25 AM, spir <denis.spir at gmail.com> wrote:

> Of course, it could be done as a function call:
>>
>> def catch(callme, catchme, returnme):
>>    try:
>>      return callme()
>>    except catchme:
>>      return returnme
>>
>> phone = catch(lambda: addressbook[name], KeyError, "Unknown")
>> but that's *really* clunky.
>>
>
I don't really find this function all the clunky.  However, it also does
not solve the case of an expensive 'except' clause that Nick pointed out as
desirable to avoid evaluating (or, for that matter, an except clause with
side effects).

E.g.

  phone = catch(lambda: addressbook[name], KeyError,
lookup_from_internet(name))




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