Re: Use of declare blocks

["Randy Brukardt" <randy@rrsoftware.com>]

<adaworks@sbcglobal.net> wrote in message
news:bByMh.11141$P47.10468@newssvr22.news.prodigy.net...
...
> When used by someone such as Randy, a programmer who
> uses every construct with care and intelligence, the declare
> block is not a primay design structure but a way of bringing
> subtle refinement to an already good design.

Richard, thanks for the vote of confidence. But I have to admit that the
above gave me a good laugh. My code tends to look just like the things you
describe you don't like (especially in the Janus/Ada compiler), especially
in regards to long subprograms. Part of that comes from the nature of
compiling: it's impossible to usefully shorten case statements with dozens
of branches. And I'm sure another part comes from Janus/Ada having started
as a university project, where things like naming and encapsulation weren't
used consistently (the latter because separate compilation was very weak in
our early tools). I just looked a couple of favorites: Gen_Name (which
generates the code for Ada "names") is 950 lines long, and it is mostly made
up of calls to other things. The root semantic routine is 2700 lines long
(it's a just a giant case statement with 378 whens at this writing: it
decides what to do with each grammar production as it is recognized).

Anyway, I do understand the readability concerns, but I think they're
overblown. If you have to look 5 pages away to find a variable declaration,
the readability of the code it is used in isn't necessarily enhanced: you're
still flipping back and forth. Moreover, trying to come up with good names
for code that are made into subprograms just to keep the code "short" is
hard, and I know I'm not good at it. These supposed helpers are a real
headache during maintenance, because its rarely obvious what they do! How do
that help readability??

                                   Randy.