Functional Programming

There is a great new Emacs plugin from Eric Merritt that like FlyMake builds your code and highlights within Emacs any errors or warnings, but unlike FlyMake builds across the whole project. You can clone the mode from here projmake-mode After cloning the repo to your desired location add this bit to your dot emacs file, replacing <PATH> with the path to where you cloned the repo. [gist]3794732[/gist] This Emacs code also uses add-hook to set projmake-mode to start for erlang-mode is loaded. ...

This will be a two part series of posts on writing plugins for Opa. One of Opa’s greatest features is you write everything in the functional, staticly typed Opa language. This even includes the frontend code you’d usually do in Javascript. This means your code is less error-prone which significantly reduces the amount of time spent on debugging code. But how do you use Javascript library X within your Opa code? ...

I received a patch for OpaDo from Francois Regis Sinot that has made the hosted OpaDo http://opado.org on Dotcloud MUCH faster, adding and removing item is now instantaneous. He placed @publish around explicitly server side functions that caused adding todo items to go from 21 to 1 server calls. I thought this simple but maybe not obvious for new Opa developers (it certainly wasn’t to me!) needed a blog post so that beginners like my self may find it and be able to start using the @publish directive. ...

ErlangDC is coming up in a month and will be featuring our own Eric Merritt speaking on building enterprise applications with Erlang and Sinan, as well as other great presentations from Erlang experts. You can still submit your own proposal. Get your tickets now!

Nicolas Glondu posted a comment on an earlier post detailing ways for doing database migrations with Opa. I thought it was useful enough that I should put up a post around it: If you have complex changes in database structures in a OPA program, you have two choices : > 1 – Keep both structure in your database and create a function which populates the new empty field from the other fields. ...

This is a continuation of two past posts (one, two) on my first application with Opa called OpaDo. You can try the live demo here and check out the full source code on Github Updating OpaDo to add user accounts the project structure has been changed a bit and modularized. Below is the new project layout. Now there is a main, todo and user module. The main module is the entry point for the app and looks like: ...