From: Alex Gutteridge <alexg@...>
Date: 2006-09-28T10:18:14+09:00
Subject: Is object[x](y,z) always invalid?

I'm working on converting a Python module (RPy) to Ruby and am trying  
to keep the api as close to the original as possible. In Python it  
(appears - my Python is very weak) that this is valid syntax:

foo[x](y,z)

Where 'foo' is an object with attribute 'x' which itself is callable  
- in this case with the parameters 'y' and 'z'. The 'foo[x]' object  
is actually an R function and some magic is subsequently performed to  
convert the parameters and call the function from Python/Ruby.

 From my experiments it appears that 'foo[x](y,z)' is always a  
SyntaxError in Ruby and the closest I can get in Ruby syntax to the  
Python is:

foo[x][y,z]

But this isn't quite as pretty, since the distinction between the  
function ('foo[x]') and the parameters 'y' and 'z' is not as visually  
obvious.

foo[x].call(y,z)

is another option, but goes still further from the Python api. Not a  
big problem for sure, but I just wanted to make sure there wasn't  
some magic trick I was missing to make the original Python ('foo[x] 
(y,z)') also valid Ruby.

Dr Alex Gutteridge
Post-Doctoral Researcher

Bioinformatics Center
Institute for Chemical Research
Kyoto University
Gokasho, Uji, Kyoto 611-0011
Japan