Exercises, examples and other material relating to training module T207. This topic is presented on public courses Learning to program in Tcl, Tcl Basics

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Tcl Programming - training course - The Tcl programming language, and Expect Tcl Programming - The Tcl programming language, and Expect This course covers the fundamentals of the Tcl programming language. You'll learn about Tcl ... http://www.wellho.net/course/tbfull.html  [course]

Learning to Program in Tcl - training course - The Tcl programming language, and Expect Learning to Program in Tcl - The Tcl programming language, and Expect This course covers the fundamentals of the Tcl programming language. You'll learn ... http://www.wellho.net/course/tlfull.html  [course]

Call by name v call by value All the programming languages that we train on provide the facility for you to write a named block of code and the call it from elsewhere - such blocks ... http://www.wellho.net/mouth/308_Call ... value.html  [short article]

Tcl - global, upvar and uplevel. In Tcl, variables are "scoped" to the procedure in which they're used. That's a sensible default, since you want to be able to write main applications ... http://www.wellho.net/mouth/1404_Tcl ... evel-.html  [short article]

Variable Scope One of the vital topics on all our programming courses is that of variable scope. Variable Scope may be defined as the area of a program in which a variable ... http://www.wellho.net/mouth/96_Variable-Scope.html  [short article]

Tcl - passing arrays and strings in and back out of procs When you want to pass data INTO a proc in Tcl from a regular variable, you write the variable name with a $ in front of it in the code and the value is ... http://www.wellho.net/mouth/2466_Tcl ... procs.html  [short article]

Passing arrays to procs in Tcl If you're writing a Tcl proc, you'll normally pass in parameters by value, specifying a $ in front of the variable whos contents you want to pass in in ... http://www.wellho.net/mouth/122_Pass ... n-Tcl.html  [short article]

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As your code grows from 1 to 10 to 100 lines, you'll find that it's helpful to split it into a series of logical blocks, each of which can be run as a command. You'll learn how to define such procedures, how to pass information in and out of them, and how to access information that's held in your main program and in the calling procedure too.

This topic is presented on public courses Learning to program in Tcl, Tcl Basics

add2	Answer to final exercise
addindemo	Sample code to complete - final exercise
cbn	Using upvar to call by name
doublit	Another upvar example for learners
dr2	Optional parameter in Tcl
dresser	Changing a value within a proc and returning the altered value
gsc	The global scope
p1	Sharing a variable using global
p2	Sharing a variable using upvar
p3	Sharing a variable using upvar and call by name - RECOMMENED
p4	returning a variable - RECOMMENED for passing 1 piece of data back
p5	Sharing a variable using uplevel - obscure!
pr1	Defining a proc (command) and using it
pr3	loading a file of procs shared with other applications
scope1	Variable default to being local
up1	Using upvar to effect a variable in the calling code
uquery	Shared file of procs
uv	Call by value and call by name
vardemo	Calling a proc with a variable number of arguments
whatandwhen	Exercise - please write the proc to complete
wwanswer	First sample answer - "getnumber"
wwbetter	Better sample answer - "getnumber"

Radia software is tailored through Tcl procedures
Teaching Tcl around the world