For one of my projects I have a python program built around the python cmd class. This allowed me to craft a mini language around sql statements that I was sending to a database. Besides making it far easier to connect with python, I could do things that sql can’t do. This was very important for several projects. However, I now need to add in if blocks for greater control flow.
My current thinking is that I will just add two new commands to the language, IF and END. These set a variable which determines whether or not to skip a line. I would like to know if anyone else has done this with the cmd module, and if so, is there a standard method I’m missing? Google doesn’t seem to reveal anything, and the cmd docs don’t reveal anything either.
For an idea that’s similar to what I’m doing, go here. Questions and comments welcome. 🙂
Hmm, a little more complicated than what I was thinking, though having python syntax would be nice. I debated building a mini language for quite some time before I finally did it. The problem primarily comes in from the external limitations. I have a bunch of “data”, which is being generous, to turn into sql. This is based on other “data” that won’t pass through. It’s also unique to each specific “version” of the problem. Doing straight data to sql would have been my first inclination, but was not practical.
For the curious, I spent a great deal of time going over the mini languages chapter in the art of unix programming, found here.
If I had built the thing in pure python, I wouldn’t have had the flexibility I absolutely needed for the problem set.
After examining the problem set some more, I’ve come to the conclusion that I can leave the minilanguage alone. It has all the features I need, and I don’t have the time to rebuild the project from the ground up. This has been an interesting problem and I’m no longer sure I would build another minilanguage if I encountered the same situation. OTOH, it works very well here, and I am loathe to give up the advantages it has conferred.