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List basics in a nutshell
Lists example from a Well House Consultants training course
More on Lists [link]

This example is described in the following article(s):
   • Lists in Tcl - fundamentals in a commented source code example - [link]

Source code: liimp Module: T206
# List basics in a nutshell

# Different ways of setting up a list
# (each of these contains three members)

set party "{Ann Marie} Brenda Charles"
set party "\"Ann Marie\" Brenda Charles"
set party {"Ann Marie" Brenda Charles}
set party "Ann\\ Marie Brenda Charles"
set party {Ann\ Marie Brenda Charles}
set party [list "Ann Marie" Brucella Charlie]

# Append adds a string (so no space)
# but lappend adds a list member (so spaced and protected)
append party Brown
lappend party Douggie

puts $party
# That prints:
# {Ann Marie} Brucella CharlieBrown Douggie

# How long is the "party" variable?
puts [string length $party]
puts [llength $party]
# It's one list. Or a list with 4 indexed members. Or a string of 42 characters

# What's the first item?
set first [lindex $party 0]
puts $first

# What's the last item?
set last [lindex $party [expr [llength $party] -1 ]]
puts $last
# surely there must be an easier way of doing that!
set last [lindex $party end]
puts $last

# Here we are looping through each item of the list
# in this example, we do NOT want to keep track of the position number
foreach person $party {
        puts "Invite $person to the party"

# Here we are looping through each item of the list
# in this example, we DO want to keep track of the position number
for {set count 0} {$count < [llength $party]} {incr count} {
        set name [lindex $party $count]
        puts "I expect person $count will come (that's $name )"


# ---------------------------------------------------

munchkin:n13tcl grahamellis$ tclsh liimp
{Ann Marie} Brucella CharlieBrown Douggie
Ann Marie
Invite Ann Marie to the party
Invite Brucella to the party
Invite CharlieBrown to the party
Invite Douggie to the party
I expect person 0 will come (that's Ann Marie )
I expect person 1 will come (that's Brucella )
I expect person 2 will come (that's CharlieBrown )
I expect person 3 will come (that's Douggie )
munchkin:n13tcl grahamellis$

Learn about this subject
This module and example are covered on the following public courses:
 * Learning to program in Tcl
 * Tcl Programming
 * Tcl Programming
Also available on on site courses for larger groups

Books covering this topic
Yes. We have over 700 books in our library. Books covering Tcl, Tk and Expect are listed here and when you've selected a relevant book we'll link you on to Amazon to order.

Other Examples
This example comes from our "Lists" training module. You'll find a description of the topic and some other closely related examples on the "Lists" module index page.

Full description of the source code
You can learn more about this example on the training courses listed on this page, on which you'll be given a full set of training notes.

Many other training modules are available for download (for limited use) from our download centre under an Open Training Notes License.

Other resources
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The Horse's mouth provides a daily tip or thought.
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• And there's a global index here.

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