[sateesh]

To me your version is less clearer than the explicit if calls:

* Name 'map' for a variable is a poor choice (as it has same name as the python builtin function map)

* Your version has off by one error, it doesn't give correct results when called with a single element list or if the list has three elements:

  >>>mymap = [
                lambda args: (0, args[0], 1),
                lambda args: (args[0], args[1], 1),
                lambda args: args,
              ]

  >>>args = [5]

  >>>mymap[len(args)](args)
    IndexError 
    Traceback (most recent call last)
    ....
   # This shouldn't be the case, a list with a single
   # element is a valid input

  >>>args = [1,6,1]

  >>>mymap[len(args)](args)
    IndexError   Traceback (most recent call last)
    ...

   # This shouldn't be the case, a list with a three
   # elements is a valid input

[saintfiends]

If only lambda's allowed statements :(.

  >>>mymap = [
               lambda args: raise IndexError,
               lambda args: (0, args[0], 1),
               lambda args: (args[0], args[1], 1),
               lambda args: args,
             ]

That aside, this approach would be much slower too.