Tcl

Syntax

Variables

Tcl supports scalar variables and associative arrays.

Variables can be assigned and read using the set command. set s {This is a string} => This is a string set n 17 => 17 set s => This is a string

Associative Arrays

set scores(Andrew) 95 set scores(Geoff) 87

The dollar ($) symbol is used to reference a previously set variable The expr keyword is used to mean evaluate and substitute.

set totalScores 0 for name (Andrew Geoff) { set totalScores [expr $totalScores + $scores($name) }

^ Java ^ Tcl ^ | i++ | incr i | | i += 2 | incr i 2 | | append s {Hello} | s += Hello |

Arrays

Control Flow

If

if {$a > 5} { set a 0 }

if {$a == 0} { set a 1 } elseif {$a == 1} { set a 2 } else { set a 0 }

Note that the start brace must appear on the same line as the if statement.

Loops

foreach i $a { }

Initialiases i to each value of last a in turn.

Andrew McDonough is a consultant CTO and software developer, currently based between Berlin and London.

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