[Python-ideas] Syntax for passing lambdas to functions

[Ron Adam]

On 02/27/2014 04:17 AM, Nick Coghlan wrote:
>  > For what it's worth, the following *could* be made to work:
>  >
>  >    spam() = fire_the_ducks(42)
>  >    f(onclick = spam)
>
> Let's talk about that for a moment. It would be a matter of making this:
>
>      NAME(ARGSPEC) = EXPR
>
> syntactic sugar for this:
>
>      def NAME(ARGSPEC): return EXPR
>
> Not what you would call a big win.

A good potential use of lambda is in constructing a dispatch table from a 
dictionary litteral or constructor.

       select = {key1:callable, key2:callable, ...}
       result = select[k]()


       select = dict(key1=callable, key2=callable, ...)
       result = select[k]()

And there is also the case of it working in a ternary if...

       result = (callable if k else callable)() #k is True or False

I think these are good test cases for evaluating usability and readability. 
  It would be nice if it worked well for each of these.

Cheers,
    Ron