New blog

I decided to move on from WordPress and start a new blog. You can read about my reasons here.

Follow me along and read my new post about Vim: How to Configure Syntastic.


I’ve been using spacehi for years. It highlights invisible characters: trailing spaces and tab characters.

Here’s how it looks if you toggle it on and off:

In my dotfiles setup, it’s turned on by default.

In most cases, whitespace characters do not matter. But sometimes they do. For example, Go and Python are picky about spaces. Also, a mix of spaces and tabs will look different for different people and their editors — because nobody can agree how many spaces at tab character is (4 or 8?!). This is something I’ve talked about before.

This week, for the second time in a couple of weeks, I lost a bunch of time on another whitespace: character 160, the non-breaking space. To make a long story short, it was a copy and paste from Skype, and the JSON parser I was using choked on it.

It seems spacehi hasn’t been touched in (almost exactly) 10 years. I found its mirror on github. But it didn’t handle non-breaking spaces, so I forked it.

I’m willing to maintain it, it a very simple Vim plugin. Bug reports and improvements are welcomed.

It’s always nice to get something for free. That’s how I feel about JSLint. Running your JavaScript code through JSLint gives you a few advantages:

  • Coding style consistency — always use ; at the end of a line
  • Syntax error detection — did you forget that ) ?
  • Logical error detection — did you forget that var?

There’s a whole bunch of stuff JSLint will pick up for you.

I have talked before about JSLint in the context of SpiderMonkey, but, nowadays, I install node.js for a few things. If I run JSLint through node.js, that means I won’t have to install SpiderMonkey anymore.

Installing Node and NPM

I admit, these pieces of software are moving fast and the instructions (or lack thereof) are limited. But these things will vary with your OS and skill level.

I’m going to focus on the Vim integration, but go ahead and install Node and install NPM.

Installing JSLint

Which one?

I recommend the simply named “jslint”. You can look it up on GitHub as node-jslint.

Make sure you don’t forget that “-g” flag with NPM. NPM changed a lot in version 1.0.

Vim Integration

The end goal is:

You are in a JavaScript file, you press F4, Vim runs JSLint on your file, parses the errors and puts your cursors on the exact location of the first error with the others one waiting in the quickfix list.

The main part of integrating with Vim to “compile” something is to set makeprg and errorformat (aka efm). If you ever need to integrate with something else, be sure to Google for those.

Since we are going to invoke :make all the time, I’m going to bind it to F4. (put it in your .vimrc)

nmap <F4> :w<CR>:make<CR>:cw<CR>

Step by step:

  • :w — save the file, doesn’t hurt if it’s already saved
  • :make — invoke make
  • :cw — open the quickfix window if there are errors. Close it if there are no errors.

Next, create $HOME/.vim/ftplugin/javascript.vim. Put these lines into it:

setlocal makeprg=jslint\ %
setlocal errorformat=%-P%f,
                    \%G/*jslint\ %.%#*/,
                    \%*[\ ]%n%l\\,%c:\ %m,
                    \%G\ \ \ \ %.%#,
                    \%GNo\ errors\ found.,

The variable makeprg is just was it invoked when you do :make. The variable errorformat are instructions on how to parse the error messages of the “compiler”. That variable and how to configure it are a whole world of complexity.

Now, restart Vim and open some JavaScript file you have lying around. Press F4. Be ready for a lesson in humility.


If things don’t work out, try this:

  • try to run “jslint” from the command-line, if it doesn’t work Vim won’t work either
  • if the output of “jslint” changes format, you’ll have to tweak errorformat

It all started with CoffeeScript. Like all languages I play with, one of my first step is to look for a Vim syntax file. Thankfully, the CoffeeScript page itself links to kchmck‘s vim-coffee-script on github. So far, so good.

Here’s the first step:

Wait … what?! I hate having to install software to … install software. At this point, I was ready to close the tab but it was a tpope project. That’s usually a sign of quality. I was ready to give this pathogen thing another look.

So … pathogen lets you dump “bundle” directories under ~/.vim/bundle/ and will setup the various Vim variables so that the plugin, ftplugin, syntax, ftdetect are all hooked up correctly. That’s nice; it solves a lot of the pain I’ve felt over the years about trying various vim plugins and messing with my setup.

In theory, you would do something like:

cd ~/.vim/bundle
$ git clone https://github.com/kchmck/vim-coffee-script.git

And add at the top of your .vimrc:

" pathogen bundles
filetype off
call pathogen#helptags()
call pathogen#runtime_append_all_bundles()

That’s pretty close to how I have it setup. While I was making my mind about pathogen, I found Tammer Saleh’s post about pathogen. Besides the details I outlined above, he suggests git cloning the repository and removing the .git instead of playing with git submodules. I could not agree more. Of course, I have to deal with that situation only because my ~/.vim is under git. (like all my dotfiles, read more)

I simplified his script for my own purposes: (on github)


refresh() {
  local url="$1"
  local dir="$2"

  rm -rf $dir
  git clone $url $dir –depth=1
  rm -rf $dir/.git

  if [ -f "$dir/.gitignore" ]; then
    rm "$dir/.gitignore"

refresh https://github.com/scrooloose/nerdcommenter.git nerdcommenter
refresh https://github.com/vim-scripts/matchit.zip.git  matchit
refresh https://github.com/tpope/vim-haml.git         &nbsp; vim-haml
refresh https://github.com/timcharper/textile.vim.git &nbsp; textile
refresh https://github.com/kchmck/vim-coffee-script.git vim-coffee-script

I think the --depth=1 on the git clone is a nice touch … especially since I delete the git directory right after the download. The CoffeeScript plugin is working well and it keeps being committed to. The refresh script is quite useful.

I’m planning on packaging a few of the plugins I wrote and “bundle” them too. (vim-slime)

2010 is over and, like last year, here’s what I read during the year:




Amusing Ourselves to Death: Public Discourse in the Age of Show Business


The Talent Code: Greatness Isn't Born. It's Grown. Here's How.


The Definitive Book of Body LanguageThe Demon-Haunted World: Science as a Candle in the DarkThe Omnivore's Dilemma: A Natural History of Four MealsExtreme Programming Explained: Embrace Change (2nd Edition) (XP Series)The Best That Money Can't Buy: Beyond Politics, Poverty, & WarBeing Logical: A Guide to Good Thinking


The Now Habit: A Strategic Program for Overcoming Procrastination and Enjoying Guilt-Free PlayThe Count of Monte Cristo (Penguin Classics)


Secrets of Consulting: A Guide to Giving and Getting Advice SuccessfullyHow We DecideThe Ten-Day MBA 3rd Ed.: A Step-By-Step Guide To Mastering The Skills Taught In America's Top Business SchoolsBrain Rules: 12 Principles for Surviving and Thriving at Work, Home, and School (Book & DVD)The Elements of Computing Systems: Building a Modern Computer from First Principles


Millennium Volume 2 La fille qui rêvait d'un bidon d'essence et d'une allumette The girl who dreamed of a can of gasoline and a match (French Language)The Road (Oprah's Book Club)Basic Economics 3rd Ed: A Common Sense Guide to the EconomyIn Defense of Food: An Eater's ManifestoThe Four Steps to the EpiphanyEat to Live: The Revolutionary Formula for Fast and Sustained Weight LossThe Alchemist


Understanding Comics: The Invisible ArtDracula


High Performance Web Sites: Essential Knowledge for Front-End EngineersAtlas ShruggedEven Faster Web Sites: Performance Best Practices for Web DevelopersLooking Backward 2000-1887 (Oxford World's Classics)Dismantling the Empire: America's Last Best Hope (American Empire Project)Flow: The Psychology of Optimal ExperienceCouchDB: The Definitive Guide: Time to Relax (Animal Guide)


Catch-22Millenium: Vol 3Ray Bradbury's Fahrenheit 451: The Authorized AdaptationRuby Best Practices


Information Dashboard Design: The Effective Visual Communication of DataUncle Tom's Cabin: Or, Life Among the Lowly (The John Harvard Library)The New PeoplemakingLolita


Scalable Internet ArchitecturesEssential SNMP, Second EditionDomain-Driven Design: Tackling Complexity in the Heart of Software


I read 42 books in 2010. That’s 8 books more than last year, or a 23% increase. I’m not sure how representative that is, however. It seems that, on average, I read about 3 books a month.

Out of those 42 books, 16 were audio books. (38%)

I was curious to know how many books, on average, I read a month. I don’t expose this information directly on bookpiles either. You could extract it from the RSS feed. It’s one the features I would like to add when I understand what information I want to present and how it is best presented.

In the meantime, I ran a query in the database and came up with this:

2009-01 3
2009-02 2
2009-03 4
2009-04 3
2009-05 3
2009-06 3
2009-07 2
2009-08 3
2009-09 3
2009-10 3
2009-11 4
2009-12 1
2010-01 0
2010-02 1
2010-03 1
2010-04 6
2010-05 2
2010-06 5
2010-07 7
2010-08 2
2010-09 7
2010-10 4

I felt 80% done. Then, I realized I didn’t quite know how I would extract, from the command-line, the sum, mean, standard deviation, minimum and maximum value. Of course, I could run it through R. Or Excel… The question wasn’t how to do statistics in general — it was how to do it as a filter … easily … right now.

A little research didn’t turn out any obvious answer. (please, correct me if I missed an obvious solution)

I wrote my own in awk. (awk is present on ALL the machines I use)

min == "" {min=max=$1}
$1 < min  {min = $1}
$1 > max  {max = $1}
          {sum+=$1; sumsq+=$1*$1}
  print "lines: ", NR;
  print "min:   ", min;
  print "max:   ", max;
  print "sum:   ", sum;
  print "mean:  ", sum/NR;
  print "stddev:", sqrt(sumsq/NR – (sum/NR)**2)

Here’s what the output looks like:

I included it in my dotfiles: the awk code and a bootstrap shell script (used above).


This project started out as a list of books in a text file.


When I think about a book, I think about its content, the people who talked about it and how it made me feel. Central to those thoughts is the visual representation of the book itself: its cover. A list in a text file was not the best way to think about books. Over time, I realized that it would be the kind of problem suited for a small web application.


I spent many hours working on this project. It used to be an excuse to play with Ruby on Rails. It used to be an excuse to play the limits of rich-client Javascript applications. It used to be an excuse to play with client and server-side optimizations, not by necessity but by a conscious effort to want to try things on a project I fully understand.

This is an application I designed for myself and that I use, for the lack of a better word, religiously. Hearing about books I want to read, buying a book, starting a new book, or finishing one, these are events that make me want to go to my profile and update it.

This application was initially meant to replace a text file. But the nature of a public display of books created new possibilities. When it comes to people I know, I want to know what they are reading so that we can talk about it the next time we meet.

“How was that book?”

Also, you can look at what people have read and discover what interests them. I have had a lot of interesting discussions after people browsed the books I have read.

Finally, this is also meant to be a portfolio piece. I can send people to the site to have a look at what I can do. The project is open-source and people can read the code and reach their own conclusions.

I’m open to comments and suggestions. Let me know what you think.

Code: http://github.com/jpalardy/bookpiles
Live app: http://bookpiles.ca