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_posts/2015-07-25-i-like-not-playing-computer.md

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+---
+layout: news
+author: Torsten
+---
+
+It really is like [Bret Victor](http://worrydream.com/#!/InventingOnPrinciple) says in his video:
+nowadays good programmers are the ones who play computer in their head well.
+
+Why? Because you have to to program nowadays. And off course that's what i'm doing.
+
+But when it got to debugging, it got a bit much. Using gdb for non C code, i mean it's bad enough
+for c code.
+
+## The debugger
+
+The process of getting my "hello world" to work was quite hairy, what with debugging with gdb
+and checking registers and stuff. Brr.
+
+The "solution", my own debugger, possibly graphical, came quite quickly. But the effort seemed a
+little big. It took a little, but then i started.
+
+I fiddled a little with fancy 2 or even 3d representations but couldn't get things to work.
+Also getting used to running ruby in the browser, with opal, took a while.
+
+But now there is a [basic frame](https://github.com/salama/salama-debugger) up,
+and i can see registers swishing around and ideas of what needs
+to be visualized and partly even how, are gushing. Off course it's happening in html,
+but that ok for now.
+
+And the best thing: I found my first serious **bug** visually. Very satisfying.
+
+I do so hope someone will pick this up and run with it. I'll put it on the site as soon as the first
+program runs through.
+
+## Interpreter
+
+Off course to have a debugger i needed to start on an interpreter.
+Now it wasn't just the technical challenge, but some resistance against interpreting, since the whole
+idea of salama was to compile. But in the end it is a very different level that the interpreter
+works at. I chose to put it at the register level (no the arm), so it would be useful for future
+cpu's, and because the register to arm mapping is mainly about naming, not functionality. Ie it is
+pretty much one to one.
+
+But off course (he says after the fact), the interpreter solves a large part of the testing
+issue. Because i wan't really happy with tests, and that was because i didn't have a good
+idea how to test. Sure unit tests, fine. But to write all the little unit tests and hope the
+total will result in what you want never struck me as a good plan.
+
+Instead i tend to write system tests, and drop down to unit tests to find the bugs in system tests.
+But i had no good system tests, other than running the executable. But **now i do**. Or rather
+i will have once the Interpreter is finished. I can just run the Interpreter on a program and
+see if it produced the right output. And by right output i really just mean stdout.
+
+So two flies with one (oh i don't know how this goes, im'm not english), better test, and visual
+feedback, both driving the process at double speed.
+
+Now i "just" need a good way to visualize a static and running program.