From: Paul Brannan <pbrannan@...>
Date: 2005-05-19T23:14:05+09:00
Subject: Re: syntax sugar: treating an object like a method

On Thu, May 19, 2005 at 02:00:04AM +0900, Eric Mahurin wrote:
> I'm thinking of yet another RCR and would like to see if
> anybody likes it.  I think this would be a sweet feature.  Here
> are the basic components:

These really sound like two separate change requests to me.

> 1. Allow a null/default method to be defined in a class so that
> the syntax "obj(*args,&block)" could be used.  obj could be any
> expression yielding a object.  When you try to treat that
> object as a method passing arguments and/or attaching a code
> block to it, the null/default method would be called.  I was
> thinking "@" would be a good name for this method - like "+@"
> and "-@".  Here are a few example uses:
> 
> * klass(*args) : you alias the null method to "new" so that
> this would be equivalent ot klass.new(*args).  I tend to forget
> the ".new" more often than I'd like to admit.
> 
> * obj() : this could be aliased to clone in Object so that
> default would be to just obj.clone
> 
> * enum {...} : you could alias the null method to "each" so
> that this would be equivalent to enum.each {...}

What you propose requires a change in name lookup rules.  I suggest you
consider what the current rules are and what you would like them to be
before you submit an RCR.

Also, consider that Ruby already has a mechanism for callable objects;
any object that is callable responds to the call() method (consider
Proc and Method).

Paul