Wednesday, May 16, 2012

It's probably been done.

I started programming in junior high, writing BASIC code on a Commodore 128. At the time the only learning resource I had was the owner's manual and some issues of Compute!'s Gazette, so I was almost completely self-taught. I don't think I had actually heard the words "computer science".

If you've never programmed in BASIC of that era, understand that:

  1. There were no "functions"; a program consisted of a list of steps, executed linearly, with some control structures sprinkled in and plenty of GOTO jumps
  2. Variables were all global
  3. Variable names were limited to two letters
There was a limited bit of "subroutine" support: GOSUB was like a GOTO that remembered where it came from, and a RETURN would start executing from the next line after the GOSUB.  But since all variables were global, subroutines couldn't be reentrant.

So I got the clever idea that instead of using variables in a GOSUB routine, you could use arrays, and then have a variable that kept track of how many times you'd entered the subroutine. Sure, you had to define the maximum number of times you expected to GOSUB before you started returning, but at least you didn't have to remember whether or not the variable you were about to mutate was going to munge a previous call.

It was brilliant.

And when I got to college I learned that I'd "invented" the call stack and recursive functions. Rather a let-down, that.

So, grab your 8502 and load up a JMP 2011, when I wrote a blog post on "Stages of Competency":
After doing "this programmer thing" for a few years now, I've noticed a pattern in how I acquire skills and techniques. It's surprisingly consistent, and consists of these stages:
I thought it was pretty remarkable how consistently I saw the progression from "awareness" to "familiarity" to "functional understanding" to "understanding" to "competence" in myself and in others.

Pretty insightful, huh?

Turns out that pattern is a simplified subset of an educational classification system called Bloom's Taxonomy.

And it was first proposed in 1956.

So, yeah, that insight you thought you just had? It's probably been done.


Unknown said...

That graphic overwhelms my feeble graphic comprehension! I think I prefer the four- (or five-, or sometimes six-) stage version of or

Tim Lesher said...

So, not only has it been done, it's been done many times over. :-)