Meme in Scala

Sebastian over at Digifesto recently alerted me to a budding meme being pushed by Eric Florenzano.  The original proposal (from here) goes like this:

Rules:

1. Implement a program that takes in a user’s name and their age, and prints hello to them once for every year that they have been alive.
2. Post these rules, the source code for your solution, and the following list (with you included) on your blog.
3. Bonus points if you implement it in a language not yet seen on the following list!

The List:

1. [Python] http://www.eflorenzano.com/blog/post/trying-start-programming-meme
2. [Bash] http://aartemenko.com/texts/bash-meme/
3. [C] http://dakrauth.com/media/site/text/hello.c
4. [Java] http://adoleo.com/blog/2008/nov/25/programming-meme/
5. [Python 3] http://mikewatkins.ca/2008/11/25/hello-meme/
6. [Ruby] http://stroky.l.googlepages.com/gem
7. [Ruby] http://im.camronflanders.com/archive/meme/
8. [Lisp] http://justinlilly.com/blog/2008/nov/25/back-on-the-horse/
9. [Lua] http://aartemenko.com/texts/lua-hello-meme/
10. [Functional Python] http://aartemenko.com/texts/python-functional-hello-meme/
11. [Erlang] http://surfacedepth.blogspot.com/2008/11/erics-programming-meme-in-erlang.html
12. [Haskell] http://jasonwalsh.us/meme.html
13. [PHP] http://fitzgeraldsteele.wordpress.com/2008/11/25/memeing-in-php-2/
14. [Javascript] http://www.taylanpince.com/blog/posts/responding-to-a-programming-meme/
15. [Single-File Django] http://www.pocketuniverse.ca/archive/2008/november/27/florenzano-factor/

For my entry, I put together a script in Scala.

import scala.Console._

var name = readLine("What is your name? ")
var age  = readLine("How many years old are you? ").toInt
(1 to age).foreach { age => println("%2d) Hello, %s".format(age, name)) }

To run, copy the code into a text file named hello.scala and then run: scala hello.scala You can get the scala interpreter from the Scala website, or your distribution’s package manager.

speaking in tongues

I recently had a chat with a friend of mine about how dissatisfied I feel that I only speak one language (one and a half, counting the few semesters of Spanish I completed in high school).  The compassionate fellow he is, my friend tried to console me, pointing out that I’m at least lucky that the one language I do speak is English (agreed) and that, considering my wealth of programming experience, I am fluent in several languages.

This isn’t the first time I’ve heard someone talk about being fluent in a programming language.  I have never met a developer in person who would use that phrasing, though.  In most programming ‘languages’ it is perfectly possible to write code in any natural language you want.  More importantly, the difference between different programming languages tends to be more along the lines of how processes are structured (if I define a variable here will I be able to see it there? change its type? delete it later? what tools are provided to help me structure data and operations on it? how many lines does it take to write 99 bottles of beer?) than the enormous differences in vocabulary that you see going from, say, English to Italian.  The ‘vocabulary’ of code, the API’s available, are something that don’t need to be memorized for a developer to be proficient; in fact I would say that hardly any developers memorize even built-in APIs (those included with the language as standard libraries) to the extent that they would learn vocabulary in a second language.

2 + 2 means the same thing in Java, JavaScript, PHP, Python, Perl, and Haskell.

I have thought about this for a while and I don’t know of a better word for a programming language than “language.”  But sometimes I really wish there was one.

Outliers in Five Minutes

Recently I was given a copy of Outliers at work to look over as inspiration for how to be effective in the new team I’ll be working with.  Or rather, a copy was purchased for my office, which I promptly took home and didn’t return for a few weeks (it’s a rather short book, when I got around to reading it, I started after dinner and was finished before lunch the next day).  That in mind, I thought the neighborly thing to do would be to summarize it for the other members of my team so they could get up to speed.  I’m putting it online so they can link to it if they so desire.

The email (slightly modified for tone and typos):

Hey guys,

Since I took ‘Outliers’ by Malcolm Gladwell home the day it arrived at the office and prevented either of you from having a chance to look at it, I thought it might be useful to provide the 5-minute version in an email.  I got the impression that Whit wanted to use this book as a framework for jteam discussions, so my notes are in the form of a table with the examples likely to be pulled from the book and the concepts for which they’d be metaphors.

Point: Sometimes we don’t know everything about a subject.
Example: In the 1950’s, medical researchers found that the populace of Roseto, Pennsylvania was much more resistant to disease than the average and after ruling out diet, exercise, and genetic disposition concluded that this must be due to the friendly, relaxed atmosphere of town life.  This was a breakthrough in medical understanding.

Point: Hidden influences can affect success as much or more than aptitude.
Example: Hockey is big in Canada.  Since the junior league tryouts have eligibility requirements including age, athletes born in January have an 11-month head start on their competitors born in December.  This is reinforced by special attention given to star athletes, resulting in the Canadian pro leagues having a preponderance of athletes born in the first quarter of the year.

Point: Excellence, without exception, requires lots of practice.
Example: Studies show that a musician needs at least 10000 hours of cumulative practice to achieve mastery.  8000 hours are required to play professionally, and 4000 is only enough to make it as a public school music teacher.  The 10000 hour requirement for mastery appears to be consistent across disciplines.

Point: It doesn’t make much difference whether you are really smart or just smart enough for the job.
Example: “Termites” (a group of children selected for high IQ by a researcher named Terman) showed little deviation from the national average for success (as measured by adult income, academic awards, etc.).

Point: People skills are important.
Example: Christopher Langan has a freakishly high IQ, but couldn’t convince schools to adjust his class schedule so that he could make the 15-mile journey to campus daily despite not having a car.  Robert Oppenheimer (also quite intelligent) tried to kill his chemistry tutor in grad school, but convinced the review board to just put him on probation.  The difference? People skills.

Point: Experience in a field that’s seeing a surge in demand is advantageous.
Example: Near the turn of the 20th century, Louis Borgenicht had the bright idea to sell aprons in the streets of Brooklyn.  Because he was a Jew and had experience manufacturing and selling clothes, he was able to work his ass off and do quite well for himself.

Point: Sometimes established giants in a field hurt themselves by turning down work that is “beneath them”.
Example: Big-name law firms did not do corporate takeovers or litigation before the 1970’s.  Joe Flom made a killing because he had been forced to work for a smaller firm (that couldn’t afford to turn away that kind of work) and when corporate takeovers became more common he was in a good position to take all that work.

Point: Some people are at a distinct advantage just because of their circumstances growing up.
Example: Children of a smaller-than-average generation do better for themselves because there is more educational infrastructure in place per-capita than preceding generations, and more jobs available per capita when they get out of school.  Maurice Janklow did poorly exiting law school just before the Great Depression; his son Mort Janklow did much better.

Example: Bill Gates had access to a real-time computing system in 8th grade and continued to get access to them pretty much constantly up to the point that he started Microsoft.  This was a pretty unique situation at the time.

Example: Bill Joy was at the University of Michigan at just the right time in order to also get access to real-time computing systems when such systems were quite rare.

Point: People’s behavior is influenced by the culture in which they grow up.  Culture is influenced by the ethnic origins of an area’s population.
Example: Psychological studies show young men from the south get more pissed off than young men from the north when similar stimuli are applied.  This is attributed to the south having ethnic origins in the Scottish highlands while the culture of the north was established by Puritan immigrants.

Point: It’s bad when authority becomes a barrier to communication.
Example: Airplane crashes are often caused by situations where the copilot is too timid to confront the captain about dangerous conditions or poor decisions.  Korean culture’s strict social structure is highlighted as encouraging this effect.

Point: Cultural predispositions affect how diligent people are and how they approach problems.
Example: Rice paddies take a lot of work to produce good yields, so Asians are very hard working people.

Example: English speakers are bad at math because the language is awkward/irregular at expressing numbers.

Point: Cultural predispositions can be overcome.
Example: KIPP (Knowledge is Power Program) schools take poor kids (usually low achievers) and make them do well in school by having 12-hour school days and 4 hours of homework nightly.  (KIPP is a middle-school level program.)

There’s not really a moral to this story; I just wanted to get that on the web.

No Crystal Ball

The OpenGeo team recently created a new, more formal group for JavaScript developers (aka the ‘jteam’) Starting this week, I was supposed to be dividing my time 3:2 between GeoServer work and jteam tasks.

The manager is dealing with some personal obligations and that first week on the new schedule was pushed back a week.

Over the winter break a neat styling tool for GeoServer was announced that made use of a GeoServer extension I’ve been working on on and off for the past 9 months or so. Since then it’s been getting a fair bit of attention from the community since then, I figured I’d be putting a lot of work into polishing it up so we could make it an official extension (basically, put a link to it on the downloads page.)

I ended up fixing random bugs against GeoServer while another developer reviewed the module.

Of those bugs, this one sounded like it would be pretty straightforward to fix. Another sounded pretty tough.

The first took me two days to fix, the second one I resolved in an afternoon.

I am beginning to think that I am not very good at predicting the future.

Happy 2009

Hey, looks like another new year is upon us (I know I missed it by a few days, but give me a break as I’ve been on vacation for a couple of weeks and my brain is still kicking back into gear.) I don’t usually put too much stock in coming up with resolutions for the new year, but this time around I think I’ll make an exception.  My resolution: complain more, but only complain to the right people.

Recently at work I’ve noticed I’m developing a bad habit of, when I have a problem with the way things are being done, complaining to everyone except the person responsible, whether because I think it’s too minor an issue to debate or the culprit is not online/around when I run into trouble or I feel like decisions have been made over my head or whatever.  While out of the office the past couple of weeks I’ve been thinking that over, and I see two big problems with that approach:

• complaining about things to others fosters a predisposition for them to find flaws with their own work, and establishes a precedent that makes following suit seem more acceptable
• not complaining to those responsible means that things won’t get fixed.  Note here that ‘fixed’ might not mean changing what’s done, it could just be giving me that extra bit of perspective that helps me understand why things are being done that way.

These two things feel like a pretty lame combo for a team, so hopefully phasing them out will be a big win.

As long as I’m doing the resolution thing, I think I will also try to post more regularly on this blog.

the right audience

I just woke up from a… wow, 2 hour-long nap.  I wasn’t planning to take a nap; I was trying to read a book about JavaScript, a programming language which interests me only due to the fact that I might eventually have some use for it.  (Not that that’s a bad reason to learn a language; there’s only one language out there that I’ve learned for a reason other than that I thought I might need to get stuff done in it; and I even take a certain glee in the raw mindless-effort-reduction capacity of some languages, a la bash:

15:56 < bmmpxf> dwins: iwilling and I are still having trouble getting
 the data in the postgis.  please stand by.
15:57 < dwins> bmmpxf: what sort of trouble? should I lend a hand?
15:59 < bmmpxf> dwins: Just trying to avoid typing in the password lots of times
16:00 < dwins> bmmpxf: parens to the rescue
16:00 < dwins> (for file in *.shp; do shp2pgsql $file; done) | psql
16:01 < dwins> man I love punctuation

Still, JavaScript the language doesn’t interest me half so much as JavaScript the platform for web application development.)

So what happened?  Was I in the wrong frame of mind (is there some sort of reading flow I should get into?)  Is my brain too feeble to handle more than 37 pages of JavaScript’s splendor without needing to recharge?  Is a book a bad way for a programmer to become acquainted with a language?  Did I miss my daily dose of wake-up pills this morning?

I think it’s just that I picked a book that was written for non-developers (from the preface: “We’re geeky, so you don’t have to be!”) and so dumbed things down a bit much.  I didn’t immediately put it down because, hey, I want to be able to explain things to non-developers too!  But after spending forty pages with half-a-dozen sidebar notes saying ’sorry we included Hello World as an example in a programming text’ and ‘html is a thing you can write in any editor, but don’t use Word!’ I was a little overwhelmed.  Why not just skim, you ask?  This particular book has so few words per page that I found skimming pretty frustrating, it just didn’t work for me.

So, moral of the story: if you read something that’s written for a target audience that clearly doesn’t include you, you’re probably going to feel like you’re going against the flow.  Similarly, if you’re writing a thing (as the OpenGeo team is right now with a serious reworking of the GeoServer documentation) you’re throwing away a lot of your effort if you don’t have the right audience in mind.

Java(Script)?

Recently my manager at OpenGeo, Chris Holmes, asked me about working on some JavaScript projects.  So far at OpenGeo I’ve been using Java pretty exclusively (I’ve spent a bit of time patching up a couple of things in Python), so JavaScript would be a pretty serious change from my normal routine.  Java is a compiled, statically typed, strongly typed language with one runtime that dominates the market (or at least, where we can specify that one particular runtime is supported by the project); JavaScript is interpreted, dynamically typed, weakly typed, and basically has as many interpreters as there are browsers out there, all of which have their own deviations from the standard.

Initially, I told Chris I’d be up for a switch of language, but when I asked some of the guys who are already doing JavaScript they told me it’d be smart to stay away if I could, because it’s just such a pain to deal with cross-browser development in JavaScript.  I’m not really that concerned about it though; I mean, don’t all languages have their weak points?  I can’t just avoid everything that doesn’t inspire outright fanboyism from its users. (Though, to be fair, there’s plenty of kool-aid drinking in the Java world as well; I just don’t have any handy examples in the form of webcomics.)

Anyway, I don’t have any JavaScript projects lined up just yet (and I do have a fair bit of stuff to do in Java), so I guess I’ll just see how things go.  Thoughts from random folks on the interwebs welcome.

(Aside for non-techies: ‘typing’ is the model by which a programming language structures data.  A strongly typed language forces you to use each value in your code as a single type (ie, is this a number or a word or a record representing a country, etc.), while a weakly typed one will try to guess the types based on context (so you can, for example, add the characters “23″ to the number 8 and get 31.  A statically typed system does all this checking before the code ever runs (and usually refuses to run if any of the checks fail) while a dynamically typed system waits until a line is run to check (and will run just fine with code that makes no sense as long as you don’t actually get to that line of code).  Wikipedia probably explains it better.  Anyway, typing is a pretty big factor in a language’s ease-of-use, since it affects how much work the compiler/interpreter can do for you in terms of validating code or figuring things out from context.)

My Very Own Branch

I’m trying something new this week: working on a slew of new features for GeoServer in a branch of my own.  It’s kind of nice to have my own sandbox, although when I finish with the new stuff I’ll be making a pretty substantial patch to the main GeoServer branch, meaning it will probably require a vote at the weekly GeoServer meeting.  Still, I’ll be able to keep my stuff separated and versioned while waiting on the 1.7.0 release, and I think the new features will be pretty exciting at the end.

What am I working on? A few things are on my plate right now:

• Make human-attended configuration for regionating a performance tweak rather than a necessity for regionating to work at all
• Experiment with some alternative ways of expressing the tree (basically, fake the inclusion of all features by drawing the first few in vector form, and including a raster background with the rest)
• Allow users to set custom templates for the KML popups on a higher level than individual layers.

<plug type=”shameless”>

If you want to help me out, you can check out the work in progress and let me know if you see anything broken in Google Earth (aesthetic opinions welcome as well!)  Just visit http://publicus.opengeo.org/dwins_kml/mapPreview.do and click on any of the KML links, then browse around.  (You’ll need Google Earth, of course; you can grab the installer from http://earth.google.com/) There will probably be another update here with more info about checking the different alternatives once I get the different visualization modes working, so stay tuned.

</plug>

Code Review Review

Mel Chua writes about code review tools in a recent blog post, pondering whether a software code review tool could benefit OLPC (where she’s now employed, doing QA and, knowing her, a zillion other things).  I was about to just make a comment there, but I realized I have a fair bit to say, so full-fledged blog post from me it is.  The only potential benefit she directly mentions is that

there’s this constant loop of feedback and revision happening with code – imagine something going around and around in a positively improving cycle – and when it’s ripe and ready, someone with privs can pluck it from that cycle and make it a commit (as opposed to a linear “go forward… get stuck here… if it doesn’t work discard it out of the waterfall completely” system).

She also links to a video of a Google Tech Talk by Guido van Rossum (of Python fame) about Google’s code review process, along with a tool he wrote to make it easier. (The open-source version can be found here.)  There, he enumerates several benefits of code review:

1. You can catch bugs before they make it into revision control
2. Senior developers can impart knowledge to n00bs
3. Senior developers can verify that said n00bs can be trusted with commit privileges (this is a big one in the open-source world)
4. Team members can familiarize themselves with each other’s strengths and weaknesses
5. In general, you get the benefits of pair programming without the scheduling constraints.

A while back we installed a trial version of Atlassian’s Crucible code review tool at OpenGeo to use for GeoServer development.  I personally ended up using it for only two reviews: a (vast) speed improvement on the code that builds regionated hierarchies in GeoServer, and to review a patch submitted by Wayne Fang of Refractions Research.  Maybe this means that constant code review is not well suited to use by smallish groups (I interact with about 4 developers who actually work on GeoServer on a regular basis, and most of the time we work pretty independently on separate parts of the project.  We are geographically dispersed, so often Important Stuff happens while I am asleep.)  Anyway, I’d say that of the benefits Guido mentioned, only the first couple really came into play.  Interestingly enough, the KML regionating work ended up being a more-or-less complete rewrite, including a new algorithm, so familiarity with the code wasn’t that important in the end.  Much of the discussion around the patch from Wayne was related to style and design concerns (does that class name really signify what it’s actually doing?) rather than behavior, so may have actually been better served by the mailing list.

A couple of other random thoughts:

• Code review is a process.  Including more process means more training needed by people coming onto a project, though this can be mitigated by restricting the complicated bits to senior members, or, ideally, an automated system.  I don’t think it’s a foregone conclusion that adding code review to a project’s policy will make it a better project; it should be considered against the weight in developer ‘activation energy.’  For something like GeoServer, where development is fairly process-heavy anyway, this is pretty marginal (and I’d be interested in seeing where a more serious trial of code review could get us.)  For something with less dependencies, less API to get acquainted with, a quicker test suite, etc, it might be overly burdensome.
• Guido also mentioned that code review will happen whether you set aside time for it or not since any bugs that make it into the codebase will have to be fixed.  It may be a better strategy to just fix the bugs that are caught in QA, directing developer attention to the most egregious bugs first.  Catching bugs by inspection is not exactly bulletproof.  Of course, if you’re relying on code review as a means of maintaining some minimal level of API design quality, going back after the fact is a bit tougher.  But then, you can review API design without going through a line-by-line audit of the code too.
• As I mentioned earlier, I work on a pretty small team.  Patches to GeoServer from developers who don’t already have commit privileges are fairly rare.  I might appreciate code review tools more if I had more occasion to assess whether or not a particular change was up to par for the project I’m working on.

quicky – unintended API design

Poking around WordPress.com today, I noticed this blog post on the WordPress.com blog about an updated theme.  It’s funny how changing something like a page template can get so much pushback from users who have somehow managed to make their blogs entirely dependent on it (take a look at the comments to see what I’m talking about).  Kinda reminds me of something I said a while back.