best practice for long method signatures with many defaults

[askreet]

I didn't see this defined in the guide, sorry if I'm just not seeing it.

The guide should define a best practice for long method signatures, like:

def do_something(os = 'precise', os_bits = 64, instance_type = 'instance-store', min_priority = 7)
...
end

For example, here are some options:

def do_something(os = 'precise', os_bits = 64,
                 instance_type = 'instance-store', min_priority = 7)

def do_something(os = 'precise',
                 os_bits = 64,
                 instance_type = 'instance-store',
                 min_priority = 7)

def do_something(
  os = 'precise',
  os_bits = 64,
  instance_type = 'instance-store',
  min_priority = 7)

[jdickey]

def do_something(
    os = 'precise',
    os_bits = 64,
    instance_type = 'instance-store',
    min_priority = 7)

Rationale: visually distinctive indentation leads the eye upward to the function/method name and, reading downward, makes clear where later statements resume.

Alternately, flag any parameter list over n (default 4?) long as a violation and recommend a parameter hash instead.

[bbatsov]

Personally, I think options 1 & 2 most appealing; 3 looks too much like a method call to me.

@jdickey RuboCop already flags methods with more that n args. I don't think that using option hashes is a good idea, since they obscure the signature of the method. Ruby 2.0 keyword args are much better idea for those that don't have to support Ruby 1.9.

[pwolanin]

I'd prefer option #2 from the OP and next (but like less) the option by jdickey