JPz'log Coin Coin and Plop da Plop

13Apr/090

Scala and DSLs

Tonight I wrote something quick in Scala to make a small DSL (just for fun).

I started with a small Email class:

class Email(name:String, address:String) {
 
  def standardForm = name + " <" + address + ">"
 
  override def toString = this.standardForm
 
}

which is really stupid: it wraps a name along with an email address, and it adds a convenient textual output form.

Now I would like to be able to write something like:

val me = "Julien Ponge" is "julien" at "gmail.com"
println(me)

To do that I wrote a simple builder:

 
class EmailBuilder(name:String) {
 
  var id:String = ""
 
  def is(str:String):EmailBuilder = {
    id = str
    this
  }
 
  def at(str:String):Email = {
    new Email(name, id + "@" + str)
  }
 
}

then an implicit conversion function:

implicit def emailBuilder(name:String):EmailBuilder = new EmailBuilder(name)

And that's it.

You should always learn new languages: they are all worth something great! Be polyglot, seriously.

By the way I heard that some of the Scala features are coming to the next major version of Groovy, which is going to be exciting!

Share this post:
  • Digg
  • del.icio.us
  • Facebook
  • Google Bookmarks
  • DZone
  • Live
  • Netvibes
  • StumbleUpon
  • Technorati
  • FriendFeed
  • Wikio
  • Twitter
  • Identi.ca
  • Reddit
  • RSS
  • Slashdot

Related posts:

  1. If you have sent me an email about IzPack…
  2. Groovy and EJBs
  3. Guice it up (or AOP can be made simple sometimes)
  4. Creating namespaces with functions in JavaScript
  5. Playing with Berkeley DB Java Edition and Guice

Enjoy this article?

Consider subscribing to our rss feed!

Filed under: English, Geeking Leave a comment
Comments (0) Trackbacks (0)

No comments yet.


Leave a comment


No trackbacks yet.

« A todo list on Google App Engine… Python IzPack 4.3.0-rc2 released »

Info

View Julien Ponge's profile on LinkedIn
Subscribe to me on FriendFeed
Fork me on GitHub

Twitter Updates

Archives

JPz'log is Digg proof thanks to caching by WP Super Cache