Ruby Method Lookup Flow

[Phrogz]

I sat down to diagram Ruby's object model in something better than
ascii, and ended up getting confused on how to label 'objects' or
'spaces' where methods lived. So instead, I diagrammed[1] the flow of
how method lookup works. I was surprised by a few findings, so I think
it was a nice exercise.

For your enjoyment and criticism, I give you:
http://phrogz.net/RubyLibs/RubyMethodLookupFlow.png

Gimme a holler if anything about it is wrong (inconceivable).

[1] Because people inevitably end up asking: it was diagrammed with
OmniGraffle, the prettiest and best damned diagramming software I've
ever used, available only for MacOS X.

 

[Mauricio Fernandez]

I sat down to diagram Ruby's object model in something better than
ascii, and ended up getting confused on how to label 'objects' or
'spaces' where methods lived. So instead, I diagrammed[1] the flow of
how method lookup works. I was surprised by a few findings, so I think
it was a nice exercise.

For your enjoyment and criticism, I give you:
http://phrogz.net/RubyLibs/RubyMethodLookupFlow.png

Gimme a holler if anything about it is wrong (inconceivable).

The unimaginable happens.

"All method lookups include, and finish at, the Object metaclass."

Object includes Kernel...
Also, s/metaclass//.

Maybe you could insert another module between Square and Rect, as in

class A; def foo; "A#foo" end end
class B < A; end
module C; def foo; "C#foo" end end
b = B.new
b.foo # => "A#foo"
class B; include C end
b.foo # => "C#foo"

in order to show that modules can shadow instance methods defined in classes
and that there's no special rule to make them float right below Object or
anything like that.

 

[Phrogz]

Excellent points, all. Updated. Reload.

 

[Phrogz]

Not to bump my own thread, but I've updated the diagram again - was
able to compress a lot of vertical space for the main diagram, and add
some informative notes calling out interesting/important aspects.

It's not (just) that I crave attention that I post this, but I really
want to make sure that there's nothing wrong or misleading with the
diagram. Having an incorrect diagram (*cough* ilias *cough*) on the web
would be far worse than having no diagram at all.

 

[Phrogz]

Oh, and: I added a PDF version of the diagram also, for those
interested in clean printing.
http://phrogz.net/RubyLibs/RubyMethodLookupFlow.pdf

I now return you to your regular signal-to-noise ratio.