Client-Side Programming with Tcl
By Chris Baron
Imagine a powerful, platform-independent language that lets you put a full GUI interface on Web page. This language has built-in security features, lots of free development tools and libraries, and is available free from Sun Microsystems. Java, you're thinking? Wrong. I'm talking about the Tool Control Language (Tcl, pronounced "tickle") in the form of a browser plug-in for Navigator 3.0 and Internet Explorer 3.0. Both the language and plug-in are produced by the Sun Microsystems SunScript group. But, you're thinking, what could Tcl possibly do for me that HTML, JavaScript, VBScript, Java, Visual Basic, SQL, C/C++, and Perl don't? Read on.
What is Tcl?
Tcl is an interpreted scripting language developed in 1987 by Dr. John Ousterhout, currently head of the SunScript group at Sun Labs. Ousterhout, along with twelve other full-time people, continues to develop Tcl at Sun. With a user base estimated at around half a million worldwide, Tcl is something of a cult classic among programming languages. It doesn't get much press, but Tcl users are true believers.
Like Perl, Tcl was originally developed as an alternative to C, to tie various applications together and perform scripting functions on UNIX systems. Tcl was also designed to be embedded into an application to provide a basis for a built-in command language. Unlike Perl, however, Tcl included almost from the start an interface to the X Window graphical-windowing system. This interface, called the "Toolkit" or "Tk," gives Tcl what Perl programmers can only dream of -- an easy way to put a graphical interface on a script that doesn't require ten times has much work as the script itself.
