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A lot of node programmers like to code on the left margin. This is made possible by JavaScript’s dynamic nature. Prototypes can be built up and exports.

In Grunt the examples and virtually all code are wrapped up in one big function. Gulp doesn’t require this, and I’m under the impression many prefer this. However Grunt has a huge standard library.

I like code that doesn’t leave the left margin for long because it’s easier for me to see chunks of code. It also allows me to interleave code, which sometimes makes a lot of sense.

Using OOP, Grunt can be made to have this style. I took the Gruntfile for jquery and made it stay to the left margin while working the same way.

I won’t be sending a pull request, but I may do this on one of my own projects.

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Update: I got it to animate all of the divs. My mistake was that I had the divs changing their position in the DOM, in addition to changing the CSS properties. Some of the divs didn’t change position in the DOM because their index was the same both alphabetically and by population, and these were animated.

I played with React some more, this time loading it from a CDN with the jsx compiler. I set the CSS properties on the divs and tried animating them using CSS3 transitions. Some are animated while some move to their new position instantaneously.

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I made a little sign-up form example with React.

I built it in RequireBin. The main react model in isn’t working in RequireBin and I’m working to get it fixed. In the meantime I’ve published benatkin-react to npm which makes the minimal changes needed to get it to work (none to the code, just to the packaging).

The sign-up form I made has validation which highlights invalid fields with red after an attempt has been made to enter it in correctly.

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This month my goal is to post a small JavaScript project every day of the month. Today’s project is an angular.js app for jumping between paragraphs using the keyboard. Besides navigating between paragraphs it can show paragraphs before or after the current paragraph without leaving the page. This could help if the reader needs to recall a detail from the last paragraph in order to fully understand the current paragraph.

I used these resources to help me get it done:

  • How to listen for key presses with AngularJS – showed me that I wanted was keydown events on the body tag using ng-keydown
  • 5apps – a lot like GitHub pages with Jekyll turned off, except I don’t need to create another branch. Unlike Heroku, free apps don’t go to sleep.
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I recently came up with a couple of pipeable perl one-liners. perl -pechop is a shortened form of perl -p -e chop. Here are the parts of it, explained:

  • perl – the perl executable, here for completeness. to learn about the options, type man perlrun into your terminal.
  • -p – perl assumes a loop around the program where it reads each line from the standard input and prints the output. since it’s a single character option that doesn’t take a parameter, it can be grouped with other options.
  • -e – evaluates (runs) the string that’s passed to it. the way perl’s option parser works, when an option takes data, it uses the rest of the command line parameter. so it can be shortened from perl -p -e chop to perl -pechop. This makes it short enough that typing it in often shouldn’t be a problem.
  • chop – the perl subroutine chop takes the current input and chops the last character off it. It’s handy for chopping the newline. For example pwd | perl -pechop will print the current directory to standard output. It can then be piped to the command to save the current directory to the clipboard (pbcopy on mac os x.

Another perl subroutine, chomp, removes the last character of a line but only if it’s the newline character. It’s useful when you don’t know if there’s a newline. The corresponding perl one-liner is perl -pechomp.

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This is a proposal for a new file format.

The TSV file format is very simple. It requires that fields be delimited by tabs, and has a limitation that tabs can’t appear within fields. Newlines are also forbidden inside a field.

The JSON file format is both simple and powerful, but it can be a tiny bit clumsy compared to TSV. Also there is a tradition of putting one JSON object on a line, but that format isn’t JSON, and it doesn’t have a name that’s caught on.

The TSJ file format is a specialization of TSV, where a field is either a JSON expression or a string. Here is how you tell if it’s a string or a JSON expression:

  1. Fields that start with “{“, ‘”‘, “[“, “-“, or the digits (0-9) are treated as JSON expressions. If they don’t parse, it’s invalid TSJ. If you want to store such a value, use a JSON string expression.
  2. Fields that are exactly one of the words “true”, “false”, or “null” are treated as JSON expressions.
  3. All other fields are treated strings.

Strings and JSON expressions are both UTF-8. Fields are not trimmed after they are split by tab characters. A file containing “true\t false\n” will be read as [[true, ” false”]].

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If you want to use Backbone.js’s extend function on your own class, all you have to do is this:

var LightModel = function(attributes, options) {
  this.attributes = _.extend({}, attributes);
}

_.extend(LightModel.prototype, Backbone.Events, {
  get: function(key) { return this.attributes[key]; },
  set: function(key_or_values, value) {
    if (typeof key_or_values == 'string') {
      this.attributes[key_or_values] = value;
    } else {
      _.extend(this.attributes, key_or_values);
    }
  }
});

LightModel.extend = Backbone.extend;

Backbone’s extend function is the same between Backbone’s classes. It just uses the prototype it was called with. MyModel1 and MyModel2 in the following example would be equivalent:

var MyModel1 = Backbone.Model.extend({});
var MyModel2 = Backbone.View.extend.call(Backbone.Model, {});
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Steve Klabnik wrote a great article called Rails has Two Default Stacks. This is the best mental model I’ve found for the major factions within the rails community.

It breaks down if you start considering various deployment options, but I realized that it’s better not to. Deployment stacks can change more rapidly, and have more reasons for needing to change, than development stacks. It is worth just thinking about the development stack, of which testing is a major part. It is the development stack that plays the biggest role in programmer happiness.

If you work on a large project, thinking about just the development side of things will probably make your (Dev)Ops people happy, too.

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Today I upgraded to rails 2.3.5 on a server that had an old version of Ubuntu. This is with an old version of ruby 1.9 that was installed using the Ubuntu packages rather than rvm. Here’s what I had to do:

1. Change the rails version

I changed the version in config/environment.rb to 2.3.15.

RAILS_GEM_VERSION = '2.3.15' unless defined? RAILS_GEM_VERSION

More information here.

2. Turn off yaml and symbol deserialization

Add this to config/environment.rb, just before the last end statement (at the end of the configuration block):

  ActiveSupport::CoreExtensions::Hash::Conversions::XML_PARSING.delete('symbol')
  ActiveSupport::CoreExtensions::Hash::Conversions::XML_PARSING.delete('yaml')

More information here. This is apparently also solved by the rails update above, but since this flaw is so harmful I’m glad to have it fixed in more than one place.

3. Require thread

I got this from a StackOverflow post. I added this to the top of config/boot.rb:

require 'thread'

# Don't change this file!
# Configure your app in config/environment.rb and config/environments/*.rb

It says not to change the file, but in this case I am not changing the file to customize my rails app but to make it work with a newer version. I’m not sure this step was necessary.

3. Upgrade rubygems

I had an old version of rubygems. It was installed with apt-get, so I couldn’t upgrade it with gem update --system. Furthermore, since I was running an old version of Ubuntu, apt-get upgrades weren’t working for me. So instead I uninstalled rubygems and installed it from source.

5. Install the gems

I installed the gems for rails with gem install rails --version 2.3.15 and also installed thin and mysql.

6. Restart the web server

Finally I restarted the web server.

Now, this is just one system configuration and chances are most are different so this may not help you. The uninstalling of rubygems and reinstallation from source took quite a while to figure out so I thought I’d share. If this doesn’t solve your problem, you may leave a comment and if I have time I’ll try to help you figure out what went wrong with yours.