nondeterministic . net

Once upon a time I thought my father was weird for using some crazy text editor that made no sense to me.

Now I have to respond to his comment(s) and defend my decision to hack up a system in sh & company because I find it easy to prototype in shell script, and I have an irrational dislike for Perl.

But I wouldn’t dream of hacking it up using anything but the latest version of that crazy text editor.

I found my missing edges (no more relying on NuSMV to flatten the Finite State Machine, something’s wacky in there), and rewrote my code in Ruby, which is a very nice language I’ve been wanting to become more familiar with and this served as an excellent opportunity. The performance increase from sh, sed, awk, and grep is unspeakably (Flying Spaghetti) Monstrous.

Now: does anyone know anything about measuring performance when your subject is shell scripts or similar? I tried Apple’s fun tools (Sampler, Shark, etc.), but I couldn’t figure out how to get useful data. The problem is that the computation is spread across hundreds of tiny little calls to the string manipulation utilities, and I couldn’t see how to convince one of the monitoring tools to create e.g. cumulative statistics including child processes, at which point I could look to the login shell for useful numbers. Ideas?

Happy day after some stuff and second night of other stuff!

This is right:

This, however, is wrong:

It is sort of cute the way ‘b’ and ‘a b’ are just hanging out there. Less cute are all the missing edges in the graph.

In other news, I need to stop writing parsers in awk and substitution evaluators in shell script. Really.

Happy something-or-other!

The November issue of Hadassah Magazine had an article on MEET, and they’ve finally updated their online archive: "Key(board) to Coexistence," by Dina Kraft.

I visited the new MEET space for the first time today, in the amorphous border between East and West Jerusalem. We have one large room and two small offices, along with an adjoining shared kitchenette, on the second and top floor of a (by appearances) recently renovated building. The skylights, sloped ceilings, and wooden joists give the place a great sort of cabin feel, but its got wiring suitable for an office.

I’m really happy about this space. I can’t wait until it’s filled with tables and chairs and computers and mentors and tutors and students.

The forms are signed and submitted and the tickets are reserved, and I’ll be going to Belgium in January for an internal conference of the European Network of Excellence on Aspect-Oriented Software Development.

So I guess this will be my first trip to the mainland.

Day 2 of the Semantics and its Applications Workshop, December 20, at Tel Aviv University.

Quantifying Interference

Avoiding Determinization

Modeling Concurrency without Global States

Lunch

Automatic Refinement and Vacuity Detection for Symbolic Trajectory Evaluation

Semantics-Directed Abstraction and Refinement

Semantic Minimizations for Temporal Logics

On the Construction of Fine Automata for Safety Properties

A Semantics for Procedure Local Heaps and its Abstractions

You have no idea the witty gems you’re missing out on if you don’t go over these with a fine-toothed comb.

The math shorthand for directed acyclic graph is DAG. And the Hebrew word for fish is "dag." So when someone asks "is that a DAG or a tree," it really sounds much more like "is that a fish or a tree?"

Which is funny when you’ve been sitting in the same chair for two days with not many fish or trees to be seen. [continue reading “Semantics and its Applications, Day 2”]

Notes from Semantics and its Applications Workshop, December 19, Tel Aviv University.

Process Extraction in a Logic of Events

Semantic Issues in the Definition of a Hardware Specification Language

Semantics of Communication Systems

A Logic of Reachable Patterns in Linked Data-Structures

Lunch

Socially Responsive Environmentally Friendly Logic

Hennessy-Plotkin-Brookes Revisited

Language Features for Program Monitoring

Notes are sometimes serious, sometimes not. There were British folk involved, so, you know. No editing has been done. No links, either; Google as needed. Continues tomorrow, with lectures more (at least theoretically) interesting to me. Maybe I’ll even format those notes better. [continue reading “Semantics and its Applications, Day 1”]

Tue Dec 13 15:01:35 2005 GMT: submitted application

maxg says:

Oy

From Boing Boing, a pointer to Holy Tango of Literature. Brilliant! And from the author’s blog, a complete copy of the text under CC license. I wonder if I’ll find this in any book stores around here…