***web programming language***

Web programming languages have a variety of ancestors: scripting languages, shell languages, mark-up languages and conventional programming languages. The resultant Web programming languages show their ancestry in their syntax, computational and data model, and implementation style (subject to the design constraints discussed in the previous section), and as a result, there are a fair number of distinct approaches taken.

Examples of Web Programming Languages

Python is a programming language that lets you work more quickly and integrate your systems more effectively. You can learn to use Python and see almost immediate gains in productivity and lower maintenance costs.
Python runs on Windows, Linux/Unix, Mac OS X, and has been ported to the Java and .NET virtual machines.

Python is an interpreted, object-oriented language developed as a full-featured, but easy to use, scripting language, by Guido van Rossum at CWI in the Netherlands. Initially developed in a Unix environment, Python is now available on PCs and Macs, and applications are portable across platforms. Python has developed a substantial, although still modest, following, as a scripting language, an application development language, and an embedded extension language. Python's design was most influenced by ABC, a little known language also developed at CWI. Python's syntax evokes C and C++, but doesn't stick too closely to those languages. Python fans tout its clear, intuitive syntax in comparison to C, C++, Java, Perl, shell languages, and most other interpreted languages, the completeness of its type system and its suitability for significant application development in comparison to Tcl , and its extensibility with Python and C/C++ libraries. Like Java, Perl and Tcl, Python offers a portable GUI library, several really. Perl advocates complain about the lack of regular expression matching and output formatting natively in Python. Perl is a little more of a sysadmin's shell language than Python, and Tcl is a little simpler and less capable. Python is more of a regular programming language, but simpler and easier to program than Java. But, all are suited to Internet programming. See Python Compared to Other Languages for a list of comparisons between Python and a variety of other languages. Safe-Python is a design for changes to add safety to Python. Grailis an web browser which supports the download and execution of Python applets in a safe Restricted Execution Mode. Grail uses the Tk GUI library.

Dylan
Dylan is a dynamic object-oriented programming language with a pascal-ish syntax, and a lisp-ish semantics. It was designed at Apple's Cambridge lab in cooperation with Carnegie-Mellon University and Harlequin, Inc., and reviewed by its potential user community, mostly former Common Lisp programmers disenchanted with C++. The goal of the designers was to create a language with syntax, performance, and executable footprint acceptable to mainstream programmers (i.e. C/C++), but with many of the characteristics Lisp programmers value in Lisp (e.g. evolutionary development, optional type declarations, runtime safety, automatic storage management, and ease of maintenance). In late 1995, Apple released its Dylan implementation for the Macintosh as an unsupported $40 "Technology Release", and then, for the most part, shut down the Dylan project, although an effort to port Dylan to MacOS on the Power PC appears to have survived. CMU has developed a byte-code compiled version of Dylan called Mindy that runs on several Unix platforms and on Windows NT, and it continues development of a native Unix compiler. Harlequin plans the release of its native compiler and development environment for Windows NT and Windows 95 in mid-1996. See The Dylan Language for a comparison of Common Lisp, Dylan, C++, and Java. Scott Fahlman states that Dylan is better suited to complex programming tasks than Java, and "can also be a good language for building safe, Web-mobile code", although I have not seen any effort to apply Dylan to the latter task.

Lingo
Lingo is the object-based scripting language for Macromedia's Director multimedia authoring system created by John Thompson. It is often compared to ScriptX, Telescript, Java, Tcl, and HyperTalk, resembles the latter most, but it is more special purpose than any of those. It is specific to Director, which is used extensively for authoring CD-ROM titles, and is not available separately, which limits its applicability to other purposes. With the release of ShockWave, a free Netscape plug-in, software developed with Director can be displayed in Netscape, and soon other browsers.

VRML (Virtual Reality Modeling Language)
VRML is a specialized language for describing 3D worlds and movement through them. VRML is the standard language in describing such scenes in the context of the Internet and the World Wide Web. As more and more sites include 3D simulations, VRML will become more omnipresent. VRML, like HTML, is downloaded from a server and executed using an interpreter on the client, just as a Java applet might be downloaded and executed. Netscape now supports such a interpreter, and there are many others.

Perl
Perl is described as a compiled scripting language. It combines elements of C with some Unix scripting and text manipulation languages (e.g. sh, awk, sed) into a more complete language that subsumes the functionality of all into one consistent whole, and is compilable, and, therefore faster than its forebears. Perl's advocates tout its ease of use when comparing it to Java, especially. One of the motivations in developing Perl was to provide an alternative to C for tasks that were a little too hairy for an existing Unix tool, or where performance was an issue. C was seen as unnecessarily low level, and C development too time consuming. Perl tries to delay the need to program at a a lower level. Its been very successful, especially among system administrators. Since CGI scripts are often built by systems folks, Perl is widely used for this, too.

compare atleast 2 PL

Python is a programming language that lets you work more quickly and integrate your systems more effectively. You can learn to use Python and see almost immediate gains in productivity and lower maintenance costs.
Python runs on Windows, Linux/Unix, Mac OS X, and has been ported to the Java and .NET virtual machines.

Dylan is a dynamic object-oriented programming language with a pascal-ish syntax, and a lisp-ish semantics. It was designed at Apple's Cambridge lab in cooperation with Carnegie-Mellon University and Harlequin, Inc., and reviewed by its potential user community, mostly former Common Lisp programmers disenchanted with C++.

simple example source code of Python

>>> class Student:
... def __init__ (self, name, age, gender):
... self.name = name
... self.age = age
... self.gender = gender
...
>>> Sue = Student("Susan Miller", 20, "f")
>>> print Sue
<__main__.Student instance at 0x81a96cc>
>>> print Sue.age
20

Within classes, you can override all standard operators, including assignment and array-indexing. Python supports multiple inheritance, class methods and meta-classes. All standard types (integers, strings, lists etc.) are classes, too, so you can subclass them and change the inherited behaviour.

simple source code of Dylan

Library declaration for a sample application using parse-arguments.
Module: dylan-user

define library sample-application
use dylan;
use format-out;
use parse-arguments;
end library;

define module sample-application
use dylan;
use extensions;
use format-out;
use parse-arguments;
end module;