BooML – Language Integrated XML in Boo

Creating XML using the .NET XmlWriter object model tends to make your code look awful. I realised that using some mackery I could make Boo support creating XML right in the language. Thus was born "BooML"

Here is a little example.

import System
import System.IO
import System.Xml
import BooML

class Book:
    [property(Title)]
    private _title as string
    [property(Author)]
    private _author as string

def GetBooks():
    return [
        Book(Title: "Foo Bar", Author: "Bob Smith"),
        Book(Title: "Test Title", Author: "Andrew Davey")
    ]    

[XmlLiteral()]
def GetBooksXml(books):
    books:
        for book as Book in books:
            book:
                @id = book.GetHashCode()
                title book.Title
                author book.Author

    
xml = GetBooksXml(GetBooks())
print xml.ToString()

<?xml version="1.0" encoding="utf-8"?>
<books>
  <book id="54267293">
    <title>Foo Bar</title>
    <author>Bob Smith</author>
  </book>
  <book id="18643596">
    <title>Test Title</title>
    <author>Andrew Davey</author>
  </book>
</books>

The magic is in the XmlLiteral AST Attribute. It transforms macros (in the example: books, book, @id, title and author) into XML macros. The XML macros then in turn create the XmlTextWriter calls.

I think this could be a really powerful language enhancement for people doing web development who want to return abitrary XML from methods.

I may start a SourceForge project to open source the development.

: 01 Jul 2006 18:06 |  Tags: Boo Coding XML |  Comments (0) |  Trackbacks (1) |  Report a problem