From: "Hal E. Fulton" <hal9000@...>
Date: 2002-06-12T07:18:22+09:00
Subject: Re: ruby-dev summary 17252-17356

----- Original Message ----- 
From: "Dave Thomas" <Dave@PragmaticProgrammer.com>
To: "ruby-talk ML" <ruby-talk@ruby-lang.org>
Sent: Tuesday, June 11, 2002 4:07 PM
Subject: Re: ruby-dev summary 17252-17356


> > In that case, what does the semicolon mean?
> 
> It separates parameters from variables which are local to the block.

[snippage]

Well, Matz is much smarter than I am... but this
makes me wince.

Complaint #1: This introduces an ordering constraint on
the items. If the "natural" order is a,b,c but we need
b to be local, we will write something like |a,c;b|

Complaint #2: The <x;y> case is exceptionally annoying
to me if I understand it correctly. Doesn't it send two 
contradictory messages (to the reader) about x? The fact
that it appears on the lefthand side of the semicolon
says it's nonlocal; but the fact it's in brackets says
it's local.

> As a somewhat tongue-in-cheek alternative (which breaks backwards
> compatibility) we could have 'do!' which inherits variables from the
> enclosing scope and 'do' which doesn't...

Sure, and let's have { and {! also...  that's even *more*
tongue-in-cheek.

I still wish we could use something other than <> for the 
new notation. At the least I'd prefer something that didn't
balance left-right (as || doesn't). But we run out of 
punctuation, don't we? On American non-APL keyboards, 
anyway.

For another less-than-half-serious suggestion: I propose
we use /.../ instead of <...>  How to distinguish this
from an expression starting with a regex is left as an
exercise for the parser.  ;)


Hal Fulton