Passing options to a function

Question

In ruby it is idiomatic to write a function that may be called like this:

open_database(:readonly) // or
open_database(:readonly, :remote, :force)

In these cases the :readonly are "symbols" and are used as "flags" to modify the behavior of the open_database call.

We would implement this as follows in ruby:

def func(*params)
  if params.include? :readonly
    puts "readonly"
  end
end

What is the idiomatic way to do this in Python?

Answer 1

There is no such syntactic sugar on Python.

---

The correct way to do this would be to use default keyword arguments:

def open_database(readonly=False, remote=False, force=False):
   # ...

You can then:

open_database(readonly=True, force=True) # remote=False (default)

---

If you want to get as close as possible to ruby, you can do argument unpacking:

def specify_flags(*args):
    return {x: True for x in args}

open_database(**specify_flags('readonly', 'force')) # Same as readonly=True, force=True