Comments on: XMLBuilder: A Ruby DSL Case Study

By: Srikanth

Srikanth — Fri, 14 Mar 2008 05:24:26 +0000

Thanks for the post. It’s really amazing. I read a lot of blogs where most of them just write pile of contents about various things but they don’t show the “code in action.” This blog mostly deals with code and that’s what makes it one of my favorite blogs of all time.

Thanks again! Keep writing!!
Srikanth

By: Jean Francois

Jean Francois — Tue, 11 Mar 2008 08:44:43 +0000

Daniel,

Ahh, thank you. I have not yet learned popular English “errors”. Thank you again.

Best,
Jean Francois

By: jau

jau — Mon, 10 Mar 2008 17:21:31 +0000

@daniel
That’s nice to hear. I’m looking forward for any info. BTW. I really like your blog. Keep up the good work

By: Daniel Spiewak

Daniel Spiewak — Mon, 10 Mar 2008 17:19:55 +0000

@jau
There really isn’t much info available anywhere. Coderspiel has done some experimenting with DSL-like constructs here: http://technically.us/code/x/the-awesomeness-of-scala-is-implicit#lets_wrap_component_construction_whiners_in_duct_tape You can also see a bit more Scala DSL techniques in this article on DZone: http://osgi.dzone.com/news/creating-domain-specific-langu

The good news (at least, I hope it’s good) is that I’ve been working on some stuff with internal DSLs in Scala, so there are a few articles coming down the pipe. The best one of them is done, but I can’t publish it right away. Hopefully soon, but watch the RSS.

@Jean
Good eye! It seems that I’ve fallen victim to that subtle difference between the apostrophy as a contraction and as a possessive modifier. The correct sentence is as follows:

“Its flexibility and intuitive nature allows developers to store just about any data in a human readable, easy-to-debug manner.”

Does this make more sense?

@Daniel
Very interesting! I hadn’t seen your post before, which surprises me. It looks a lot like how functional languages construct trees, which seems fairly intuitive to me. I’ll have to give this a closer look.

By: Daniel Schneller

Daniel Schneller — Mon, 10 Mar 2008 12:39:25 +0000

Something similar is possible in Java, too. I blogged about this some time ago: http://dschneller.blogspot.com/2007/08/building-xml-groovy-way-in-java.html

In the meantime I have improved (internally) upon that by providing static methods that wrap the different constructors. The benefit is a “lighter” syntax. By statically importing those factory methods, you can get rid of all the “new XElement(” stuff in my examples and instead just write code like

elem(“parent”,
elem(“child1″, “value1″),
elem(“child2″, “value2″)
)

(hope this is readable in the comments).

However one has to admit, that the ruby source is way shorter than the implementation of XElement and XAttribute.

By: Jean Francois

Jean Francois — Mon, 10 Mar 2008 11:22:41 +0000

Pardon me. English is not my first language. Can someone please explain what this means:

“It’s flexibility and intuitive nature allows developers to store just about any data in a human readable, easy-to-debug manner”

I expanded the contraction (?) to:

“It is flexibility and intuitive nature allows developers to store just about any data in a human readable, easy-to-debug manner”

but that does not make any sense to me. Any help would be very welcomed. This article looks great, but I cannot understand it all

By: jau

jau — Mon, 10 Mar 2008 08:09:12 +0000

Hi,

Maybe you know where can I find some info about internal DSLs in Scala? I have been looking on google and nabble but there is not that much information. Or maybe you know at least some libraries using such concepts? I would be highly interested.

Thanks,
Mateusz