[Jython-users] Dynamic scripting at JAOO

[Frank C. <fc...@pu...>]

JAOO had an entire scripting track this week. Here's an exceprt from =20
my blog at http://www.xquerynow.com on the opening day's events on =20
scripting. -Frank

The Joy of Scripting

=93Dave Thomas=94, http://www.davethomas.net opened the scripting track =20=

with a good summary of the basics that all of the scripting languages =20=

(Jython, Ruby, Groovy, PHP, etc.) use. Dave categories scripting =20
languages into two types: those based on prototypes and those based =20
on classes.

Class based scripting languages define a factory to instantiate an =20
object through invoking a constructor: Class new. These classes =20
inherit from other classes by subclassing. Most use super to =20
reference methods in the super class.

Prototype based scripting languages create new objects by cloning an =20
existing object. These languages use a prototype for method sharing. =20
When a method is called in a prototype that does not exist in the =20
current object then the language tries to find the method by =20
following the prototype chain.

Dave talked about the reason for scripting languages to exist by =20
talking about PHP. Dave said, =93PHP is the most ugly language in =20
existance, prior to PHP was DBase II, then FoxBase.=94 According to =20
Dave, PHP=92s greatest contribution is to make complicated low-level =20
calls in Linux easy. (Dave also provided great priase for PHP 5 for =20
getting a real class model.)

Dave is full of salty comments, including, =93Just say no to multiple =20=

inheritance and generics. These were added by language scientists so =20
that only they would understand the language.=94

Dave pointed to examples of successful script language use. He noted =20
that Python is the language behind the =93Swig=94, http://www.swig.org =20=

game site. In that case the client to =93www.taikodom.com=94, =20
www.taikodom.com is a Python client. In this example, the client =20
talks to an engine implemented in c for performance reasons.

-Frank

---
Frank Cohen, Raining Data, http://www.xquerynow.com, phone: 408 236 7604
Author of "Java Testing and Design: =46rom Unit Tests to Automated Web =20=

Tests"
from Prentice Hall, details at http://thebook.pushtotest.com