Exercises, examples and other material relating to training module T213. This topic is presented on public courses Learning to program in Tcl, Tcl Programming, Tcl Programming

As your code grows, you'll want to divide it into series of modules. These are known as packages in Tcl. You'll also want to use a separate namespace so that procedure names in one package don't conflict with the same procedure name in another. Libraries allow you to load code in C as well as Tcl into your interpreter.

Articles and tips on this subject		updated
4522	Loading packages in your Tcl program In Tcl, extra bundles of code can be loaded from packages which are files of more ... brought in with package require from a folder that's listed in the auto_path variable. Packages are defined with a package provide in the source code of the package which must be indexed in a file called pkgIndex.tcl. ...	2015-10-09
3417	What is a namespace and why do we need them? We name variables. We do it so that we can identify specific pieces of data by a key, rether than have to give some longer sort of identification description when referring to them. We don't refer to "the patriarch of the household" = we refer to Zeb. And we refer to Esther, John and Olivia, Jason ...	2011-09-03
3418	Tcl packages, pkg_mkIndex, pkgIndex.tcl -what are they and why use them. In the previous article [here], I wrote about namespaces and how - as our program grows - we need to keep named pieces of code and globally accessible variable in their own groups. And we do so using a structure that's very much like family names and forenames. As our program grows, we also need to ...	2011-09-03
3066	Separating groups of variables into namespaces If your program's going to grow in size beyond a certain point, you'll need to use some sort of namespace or package to segment global names into different groupings - moving from a single name to a forename / surname type system, if you like to think of it that way. In C++, it's namespaces - see [here] ...	2010-12-04
1529	Tcl - learning how to use namespaces, packages and libraries together Tcl supports both packages (which allow code to be loaded from libraries at run time) and namespaces (which allow for procs and variables to be grouped together to allow you to avoid conflicts as you use code from lots of different sources). Strictly speaking, the two sets of facilities are independent ...	2008-02-02
1339	Packages and Namespaces are like Suitcases and Aircraft Are Suitcases and Aircraft the same things? No, clearly they're not, but you'll often use them in close assocoation with one another. When I was in Albany, New York State, the other week ... I travelled there from Melksham with a suitcase of luggage, and I used an Aircraft for my journey. Taking ...	2007-09-11
146	example of Tcl namespaces and packages Packages in Tcl allow you to define a file of code that's going to be loaded as required at run time. Namespaces allow you to define a new set of variable and proc names that doesn't conflict with the variable and proc names in your main program - rather like giving all the variable and procs in part ...	2006-06-05

2wice	Using a package that contains a namespace
dinpack	Using packages and namespaces together
doubler.tcl	define a package to contain a namespace
gpack.tcl	package goose - goes with dinpack
legals.tcl	Definition of a package
nex	packages with and without namespace
ns_exim	Namespace export and import
ns_no	shows how variables are lost between proc calls
ns_up	Variables saved between proc calls in the next code level up
ns_y2	Counting proc calls using a namespace - shorter example
ns_yes	Saving variables in a namespace
nsp	setting up and using a namespace
nsq	Adding a package to a namespace
packs	Loading a package
rules.tcl	Definition of a package with namespace
show.tcl	Defining a package
tabby.tcl	a namespace wrapped in a package
toes.tcl	Package to go with twice demo
tpack.tcl	package chicken - part of dinpack demo
twice	Using a package - without namespaces
updown	uplevel - performed in calling code variable space

Public Tcl course