Comments on: Crufty Old Perl

By: ollyg

ollyg — Fri, 12 Mar 2010 18:53:47 +0000

Hi Alexei,
You are right, many people are blind to the limits of their favourite technology. The irony is that all these modern dynamic languages and frameworks have borrowed from each other over the years, leap-frogging along the way.
If someone said to me that Django or Rails was better than Catalyst I would reply asking why they think that’s the case. Perhaps Catalyst is missing a feature and a patch could be written.
I think Catalyst is quite different to Rails anyway, and cannot be compared directly as they focus on very different aspects of web app programming. Each has its strengths and weaknesses.

By: Алексей Капранов

Алексей Капранов — Fri, 12 Mar 2010 10:01:07 +0000

I’ve heard several times that Django and Rails are really better than Catalyst. Friends of mine complained to me that they love Perl and would very much prefer to code in Perl if there were Django-style framework available alongside Catalyst.
Is Catalyst really on par? It’s too bad people rarely use both Catalyst and Django/Rails.
Total converts usually praise the tech they converted to even if they secretly regret.

By: Dave Cross

Dave Cross — Fri, 12 Mar 2010 08:34:35 +0000

Oh, I agree completely. Rewriting from scratch is generally not a good approach for the reasons that you mention. But if you’re going to suggest a rewrite in Rails or Django then you should at least consider rewriting it in Catalyst as well.
The approach we’re trying to take on one of my current projects is to replace old and crufty pieces of code with new, shiny code that does (approximately) the same thing. We’re often running the old and new code alongside each other for some weeks until we’re sure that the new code is doing all the right things. Then we chop out the old code.
The danger with this approach is that sometimes that final stage gets forgotten. We’re trying to ensure that doesn’t happen.

By: ollyg

ollyg — Fri, 12 Mar 2010 08:31:50 +0000

To add to your point about there being a lot of bad Perl out there… this can explain the liking for Django, Ruby, etc, which I’ve also encountered.
Those new languages and frameworks don’t yet have that mass of stinky old legacy code. They will one day, and then those same people suggesting Ruby today will be suggesting the next new kid on the block!
Switching language is, in general, a false economy.

By: szabgab.com

szabgab.com — Thu, 11 Mar 2010 21:01:15 +0000

If I understand you, you say that rewriting the old crufty Perl code now that you already understand the business can dramatically improve the maintainability of the code.
Of course using a modern framework with a (post)modern object oriented system will make it even more maintainable.
These attempts to rewrite a huge code base often fail even before they are started as management gets afraid of the size of the project but leaves your programmers longing for that modern language/framework.
So maybe the strategy should be to recommend rewriting it in Modern Perl with Moose and Catalyst. Likely that initiative will also fail (due to lack of time) but at least people will want to move to Moose and Catalyst.