Incr Tcl

Itcl

Paradigm	multi-paradigm: object-oriented, functional, Imperative, event-driven programming
Designed by	Michael McLennan
Developer	Michael McLennan
First appeared	1993
Stable release	Itcl4.1.1 / 21 December 2017 (2017-12-21)
Typing discipline	dynamic typing, everything can be treated as a string
License	BSD-style
Website	itcl at SourceForge
Influenced by
Tcl, C++

incr Tcl (commonly stylised as [incr Tcl], and often abbreviated to itcl) is a set of object-oriented extensions for the Tcl programming language. It is widely used among the Tcl community, and is generally regarded as industrial strength . Its name is a pun on "C++". Itcl implementations exist as both a package that may be dynamically loaded by a Tcl application, as well as an independent standalone language with its own interpreter.

Overview

Features

Namespace support

Itcl allows namespaces to be used for organizing commands and variables.

Example:

package require Itcl
    
itcl::class Toaster {
    variable crumbs 0
    method toast {nslices} {
        if {$crumbs > 50} {
            error "== FIRE! FIRE! =="
        }
        set crumbs [expr $crumbs+4*$nslices]
    }
    method clean {} {
        set crumbs 0
    }
}
    
itcl::class SmartToaster {
    inherit Toaster
    method toast {nslices} {
        if {$crumbs > 40} {
            clean
        }
        return [chain $nslices]
    }
}
    
set toaster [SmartToaster #auto]
$toaster toast 2

C code integration

Itcl (like Tcl) has built-in support for the integration of C code into Itcl classes.

See also

• OTcl
• XOTcl
• Tcllib
• Itk
• Tk (framework)

References

incr Tcl from the Ground Up by Chad Smith, published in January 2000.

This is a complete reference manual for incr Tcl, covering language fundamentals, OO design issues, overloading, code reuse, multiple inheritance, abstract base classes, and performance issues. Despite its breadth, it follows a tutorial, rather than encyclopedic, approach. This book is out of print as of September 2004.

External links

• Itcl/incr Tcl project page
• Tcl package site
• tclweb project (there is a mailing list maintained at this site)