From: Tim Bates <tim@...>
Date: 2003-11-07T18:36:49+09:00
Subject: Re: ruby-dev summary 21637-21729

On Fri, Nov 07, 2003 at 06:04:47PM +0900, Laurent Sansonetti wrote:
> I think it's always better to avoid operators in the end of lines (code
> is therefore more readeable).
> 
> But AFAIK && unfortunately, Ruby does not handle this kind of syntax yet.
 
Because of Ruby's line-based syntax, Ruby guesses that if you have hit
the end of the line and the line as a whole is valid, then you have
finished that statement. This is essentially a limitation of the parser.
There are two ways around this - require statements to end with a
special character (eg a semicolon) so that if we get to the end of the
line and haven't found that character yet we know the statement isn't
finished, or implement look-ahead in the parser to take a look at the
next line and see if it, when combined with the current line, is a valid
statement as a whole.  This is a lot more difficult; it involves
look-ahead and creates a whole new family of ambiguities; e.g. what do
you do if the next line creates a valid statement when combined with
this line, and also the two lines are valid statements by themselves? So
if the alternative is to require every statement to end in a semicolon
(noooo!) which takes a significant chunk out of the beauty of the
language, I must say that I prefer the way it is done now - and the same
applies to most of Matz's decisions, which is why I love this language.

Tim Bates
-- 
tim@bates.id.au