Saturday, April 20, 2013

Program config as a DNA strand

This is a technical followup to the post about mind-altering programming languages, which concentrates, iterates and extends on the abstract DNA part.

Do you know how DNA looks like from the point of view of Python programmer?
DNA is a list. Of genes, and fillers in between.

    [ GENE, GENE, GENE, None, GENE, STUFF, GENE, .... ]

By the analogy with software, one GENE is one option. Here None or STUFF is something that is not recognized and not used in the process right now, but may be used later even in a different place for a different purpose. This leads to very interesting properties of configuration described as a DNA strand.

Property One: Everything is Optional and Configurable

Usually it is a tough choice what to include into your program config, because an option a day keeps users away. But with DNA config it doesn't matter - you can encode everything - every bit of flexibility you wanted, every feature-creeper, forward-thinking matter. Don't bother yourself with restrictions - include everything.

Property Two: Indefinite Logical Groups and Namespaces

To make sense out of tons of information in a DNA strand, you need to concentrate only on the parts that are relevant to you. This is done by "masking" (or marking) parts of the DNA code according to your current task. When you apply a mask, all GENEs of DNA that are not used are cleared. You can have multiple masks for different programs. An awesome feature-creeper would be to figure out mask automatically during the program run (program explicitly marks sequences what it reads and what it skips).

Property Three: Non-linear Option Identification

Because DNA is a list, you may think that you need to know option position to access it. This is not necessary. Index in a DNA is the most straightforward way to lookup an option value, and mask is a tool to help explore and identify its position. But the true power comes from the fact that a option can be identified by just analyzing content. Option can be a single GENE in specific format, or it can be identified as a sequence of GENEs that pass some validation logic. This makes is possible to write generic configuration analyzers, which can read these sequences to detect configuration problems, patterns and meaningful values to produce nice visualization out of them.

Property Four: Application Types

In real world DNA is packed in chromosomes. Humans have 46. Potatoes possess 48. Zombies are somewhere in between. In a virtual world of coding it makes sense to use one chromosome per application type. For example, every Python web framework has a lot of common parts, common features and minor details in these features, so a variety of such frameworks can be encoded with a single DNA strand.


It may sound too abstract, but try to think how to build a shared DNA strand for two or more mini web application frameworks in Python. Just remember that DNA code includes both hardcoded application features and modifiable configuration options. And as usual look at BoxCar 2D for an inspiration.