Question

I’m new to python and I really like concept of using dictionaries instead of switch/case statements, but there is one problem I can’t figure out

Let’s say we have a ‘pythonic case’ statement

{
    'a': somemethod,
    'b': othermethod
}['a']()

This works fine, but I can’t figure out how to run some block of code like in other languages like java, something which would look like this

{
    'a': { some commands here }
    'b': { other commands here that are executed }
}['a']

Maybe lambda could help?

Thank you so much

Answer 1

Dictionary values have to be objects of some kind. This means that you essentially must encapsulate the code you want to run within a function defined elsewhere. You could toy with exec — you could create a dict of strings, and then exec a string from the dict, for example — but I wouldn’t recommend it.

lambda does partially answer your question, but lambda is limited in its applicability; it can only create one-line functions, among other limitations. Still, for very simple functions, it is adequate.

>>> d = {
...      'a': lambda: 5 + 5,
...      'b': lambda: 10 + 10
...     }
>>> d['a']()
10

The best way to do this with longer blocks of code is simply to define a function or method.