From: Isaac Gouy <igouy@...>
Date: 2005-10-01T02:31:45+09:00
Subject: Re: Large Ruby Apps ?

Kent Sibilev wrote:
> I don't agree. Static analysis captures errors that are not usually a
> big problem.

That's a huge generalization - can you substantiate it?

afaict a trivial error can be a big problem when it causes a failure
that has significant consequences.


> If your unit tests have enough coverage they will capture
> all these errors

If I was as good a programmer as my ego pretends I wouldn't make any
errors and the whole issue would be moot.

If I was as good a programmer... I would have unit tests with enough
coverage (and I wouldn't have made any errors writing the unit
tests)...

Errare humanum est.


> but static typing makes your programs too noisy since you have to feed your
> compiler with a lot of crap.

The comment was about "static analysis" not about "static typing".

Here's an example of static analysis of source code written in the
dynamically typed language Erlang:
Detecting Software Defects in Telecom Applications Through Lightweight
Static Analysis: A War Story
http://user.it.uu.se/~kostis/Papers/bugs05.pdf
http://user.it.uu.se/~kostis/Papers/war_story.pdf


Here's an example of static analysis of source written in C:
SLAM and Static Driver Verifier: Technology Transfer of Formal Methods
inside Microsoft
http://www.cse.ogi.edu/~byron/papers/history.pdf


> Very good example of
> how bad it could be, check out java with generics. By increasing the
> size of your program you increase the possibility of making a mistake
> and your program becomes harder to read.
>
> Kent.
>
> On Fri, 2005-09-30 at 22:00 +0900, slonik.az@gmail.com wrote:
> > Very useful discussion that highlights quite few misconceptions.
> > So far in this thread posters were contrasting "old school" static
> > type and variable checking versus Ruby's dynamic nature with run-time
> > Unit Testing properly done. The truth of the matter is that a
> > programmer's life is easier when one has both:
> >
> > 1: Static (aka compile time) program analysis that captures many
> > "human" errors like typos, obvious flow control flaws, etc.
> > 2: Dynamic, run-time program verification consisting of unit tests and
> > integration tests.
> >
> > Ruby clearly lacks static analysis tools.
> > 
> > Just my 2 cents