Tcl
Est. read time: 1 minute | Last updated: September 23, 2024 by John Gentile
Contents
Environment
Tcl can be easy installed with most package managers and may already be on a given system. The command line interpreter can be run in the shell as $ tclsh [script]
to run a Tcl script or, when no arguments are passed, can run as an interactive shell to run Tcl commands.
Command Reference
Standard Output
puts
is used to print text to standard output and comments are signified by #
characters.
puts "Hello, World" # comment
# comments can also happen directly after semicolons
puts HelloWord; comment after semicolon
Assigning Values to Variables
Tcl is a quick and easy language for scripting since it is weakly typed; values and variable assignment types can be inferred without explicit conversions. In Tcl the set var val
command puts the contents of val
in the memory space of the first argument var
. $
is used to tell Tcl to use the value of the variable.
set X "string value"
set Y 3.14 # numeric value
puts "The value of Y is $Y"
The \
backslash character is used to escape variable substitution for example:
puts "\$X" ;# outputs the string literal "$X" instead of the value in the variable `X`