Big rewrite: C++ to django(blog.awarelabs.com)
blog.awarelabs.com
Big rewrite: C++ to django
http://blog.awarelabs.com/?p=67
2 comments
If it's very cut & paste code, then large amounts of code can be rewritten with appropriate tools. The Rewrite Tool from the Smalltalk Refactoring Browser can be used this way. I once rewrote 2500 "Database Transformers" for a single "change request" this way in just a few days. Each one of those took up 2/3rds of a page printed out. I decided to do this, because these "transformers" were defined with code blocks, and clueless programmers were shoving business logic into them. I discovered that about half of the blocks fit about a dozen repeated patterns. The Rewrite Tool lets you do syntax directed translations with wildcards that can be used in the generated code. I wrote a small hierarchy of Database Relation objects that also understood what to do with simple attribute values, and created syntax directed rewrites.
We put the thing into production next release. Something crashed every client on the production floor -- we discovered that clueless programmers had put a fix to the business logic (1) into the guts of the "Database Transformer" framework. We moved that code over, and after that everything just worked!
(1) - On top of that, this case wasn't covered in the tests! I was glad to have left that shop.
We put the thing into production next release. Something crashed every client on the production floor -- we discovered that clueless programmers had put a fix to the business logic (1) into the guts of the "Database Transformer" framework. We moved that code over, and after that everything just worked!
(1) - On top of that, this case wasn't covered in the tests! I was glad to have left that shop.
he said he cut and pasted code from other projects, so no way to know how much code he typed in that day.
I don't think that he wrote ~6k lines of code in 12 hours. He said that he "will cheat a bit and just wholesale steal entire chunks of code from my other projects." If you look at the first two hours of time they were not spent writing much code at all mostly debugging sql schemas and the like.
He did copy code from another project. But still...
Why did this have to be done in twelve hours?
Those Django kidnapping gangs are upping their ransoms these days what with inflation and so forth.
Probably he just wanted to get it done in 12 hours.
I'm not sure what to think of it. Can someone really be that productive in producing (mostly) debugged quality code? Or maybe he did a mostly literal translation so that the logic wasn't refactored much.
edit: yeah, he cut-and-pasted, that's what I was hinting at when I said "quality code". He could have taken two days to do it instead and properly abstract out the relevant parts. Otherwise, it's not a rewrite, it's just a translation from one language to another.