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Sunday, July 12, 2015

Agile Development

I've been improving my template comparison tool over various iterations, as I have been prone to do most of my life as a software developer.  It never really occured to me that I use agile without really thinking about it in projects like these.  Since I'm both the audience, and the developer, I try something out, and see where it goes.  I start with something that minimally works, or is at least good enough to start with.  Then I look at it, and see what I want to make better or improve upon.

The tool has evolved in various stages.  I started with basic comparisons over the narrative text of the constraints.  I made some changes to remove some non-essentials from the text comparison when I first built it, e.g., conformance identifiers.  Subsequently (after implementing a few other tweaks), I realized that I could further improve that comparison by simply removing parenthetical text.

In between those tweaks, I fixed my context "bug", where I hadn't counted on the fact that that same context could be constrained in different ways.  Originally, I just iterated through all the variations, but found that two different contexts that should have lined up (entryRelationships where typeCode='COMP'] didn't, simply because of ordering issues.  So I then sorted those contexts differently, using typeCode.  I later realized that wasn't good enough, because I was comparing an entry of type Act to another of type Procedure.  So, now I look at both @typeCode and @class.

But adding typeCode and class to the context makes the output ugly, and I really don't need to see this stuff, just organize by it.  So I'll have to change my output to eliminate text between [] in my rewritten contexts.

It's still not perfect.  One of my current challenges is that while I want to keep my comparison table columns aligned between templates, I also want to support indenting of nested constraints in some way.

outer context constraint 1Old stuffNew Stuff
outer context constraint 2Old stuffNew Stuff
inner context constraint 2aOld StuffNew Stuff
inner context constraint 2bOld StuffNew Stuff

The problem is that I don't know how many rows of inner constraints will be produced until I produce the output.  So I cannot compute how many rows I need to span value for the empty cells in the inner context.

There are at least three ways I can think of to resolve this.  The simplest of these is to apply a second pass transform over the output to clean up the context breaks.  I can simply output a tag in the recursing section of the table, and then count rows and compute how to clean it up.  See there?  I've done it again.

Well, it's about bedtime (I'm in Budapest for the next three days), so I better finish up and get some sleep.


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