From: Mark Hahn <mchahn@...>
Date: 2002-01-05T15:47:03+09:00
Subject: [ruby-talk:30272] Re: Indentation (was: should I use ruby instead of perl)


All six ends could be left off with no ambiguity.  The EOE is grouped into a
string at a low level, so it is parsed seperately from the outer code.  The
first three ends would be added by the parser when the string eval happens
and the last three at the main eval.

You must admit that 6 ends in a row conveys no information to the reader.
That is my definition of noise.  If you think that use of the vertical space
is "prettier", then I cannot argue with that.

-----Original Message-----
From: David Alan Black [mailto:dblack@candle.superlink.net]
Sent: Friday, January 04, 2002 10:27 PM
To: ruby-talk ML
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