From: dblack@...
Date: 2006-07-05T20:00:08+09:00
Subject: Re: About 1.9 #__method__ feature.

Hi --

On Wed, 5 Jul 2006, Yukihiro Matsumoto wrote:

> Hi,
>
> In message "Re: About 1.9 #__method__ feature."
>    on Wed, 5 Jul 2006 06:26:14 +0900, ara.t.howard@noaa.gov writes:
>
> |>  obj.funcall(:foo, 5)  # Success. funcall can call private.
> |
> |what improvement does that give over
> |
> |   obj.instance_eval{ send :foo, 5 }
> |
> |??
>
> Succinctness.

Until people start saying, "Wait -- I thought these things were called
'methods' in Ruby.  What's a 'function'?  Is it a method?  Is it just
a method without an explicit receiver?  And does that mean you can
never 'funcall' a setter method, since they *always* require an
explicit receiver?  But when you 'funcall' a symbol, you're not using
method-call syntax anyway, so the idea of an 'explicit receiver' is
irrelevant and meaningless.  Is there a 'function' method, similar to
'method' but including private methods?  But why are private methods
called 'methods' at all, if they're 'functions' in 1.9?...."

Then it gets less succinct :-)  I'm afraid I still don't know the
answers to these questions.  I do understand the "functional style"
method call (though I don't understand how it relates to "funcall",
since funcall isn't done in a functional style).  But I've always
thought that functional style was one of these things that grew
organically out of the design of the language, without having to be
named and ingrained at the language level:

     method call
   + situation where implied receiver can (or must) be used
     ----------------------------
   = functional style

Now it seems like this:

     method call   <--------------------------------
   % explicitness of receiver                       ^
     ------------------------                       ^
   = whoops -- "method" should have been "function" ^

and also:

     obj.funcall(:meth)
   % if this were a lexical method call,
       would the receiver have been explicit?
     ----------------------------------------
   = decision whether "funcall" was calling a method or a function

It all seems so non-linear, doesn't it?


David

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