[Python-ideas] combining two threads: switch statements and inline functions

[Andrew Barnert]

On Feb 11, 2014, at 15:45, Chris Angelico <rosuav at gmail.com> wrote:

> On Wed, Feb 12, 2014 at 10:05 AM, Bruce Leban <bruce at leapyear.org> wrote:
>> What if we had the ability to write dictionaries with inline functions in
>> them.
>> 
>> def sample(i, op, j):
>>    switcher = {{
>>       '-':: if i > j:
>>                 return i - j
>>             else:
>>                 return j - i;;
>>       '+':: return i + j;;
>>    }}
>>    return switcher[op]()
>> 
>> 
>> Please don't pay attention to {{ :: ;; }} which would never be the actual
>> syntax or what this code is doing (nothing useful) or whether i or j should
>> be passed as parameters rather than closure. This is equivalent to:
>> 
>> def sample(i, op, j):
>>    def diff():
>>        if i > j:
>>            return i - j
>>        else:
>>            return j - i
>>    def add():
>>        return i + j
>>    switcher = {
>>       '-': diff,
>>       '+': add,
>>    }
>>    return switcher[op]()
> 
> Hmm. In terms of scoping rules and so on, would it be cleaner to
> instead make it more equivalent to a big fat expression?
> 
> Hmm. In terms of scoping rules and so on, would it be cleaner to
> instead make it more equivalent to a big fat expression?

That just means it's a lambda form without the lambda keyword, right? That's certainly cleaner, but I'm not sure what it buys.