From: David Alan Black <dblack@...>
Date: 2002-01-05T15:27:21+09:00
Subject: [ruby-talk:30269] Re: Indentation (was: should I use ruby instead of perl)

Hi --

On Sat, 5 Jan 2002, Mark Hahn wrote:

>
> If the tail end (line going left) is all 'end' and '}' lines, then it could
> look like this:
>
>
> \
>  \
>   \
>    \
>     \
>      \
>       \
>       |
>       |
>
> which is much shorter.  The reason is that if you hit the end of the file,
> or a def, module, or class keyword, all closing lines could be inserted by
> the compiler for you, instead of giving an error like it does now.
>
> I discovered this trick a long time when TI claculators would allow input
> such as:  (5*(3+2  (no closing parens were needed).
>
> I hate it when I see a third of my lines filled up with closing lines
> (noise), and I don't like the column restrictions that Python forces on you.
> This solution would have the clean look of python without the column line-up
> restriction.

<disclaimer> I actually like having end and } tokens, and do not
advocate getting rid of them.  So this response, for me, is just
for technical interest :-) </disclaimer>

I'm not sure how a parser operating as you describe would be able
to handle something like this:

module Outer
class Thing
def initialize
instance_eval <<EOE
def some_method
class << self
def other_method
puts "hi"
end
end
end
EOE
end
end
end


without the 'end' keyword.  (I've deliberately kept it left-justified
so as to highlight the jumbledness from the point of view of relying
on def and class to trigger implicit 'end's.)

I don't know enough about parser-writing to speak with complete
conviction on this... but if my impression is right, then the end and
} tokens really aren't redundant (i.e., aren't noise) in Ruby, because
they make things possible that otherwise wouldn't be.


David

-- 
David Alan Black
home: dblack@candle.superlink.net
work: blackdav@shu.edu
Web:  http://pirate.shu.edu/~blackdav