append — Append to variable
append varName ?value value value ...?
Append all of the value arguments to the current value of
variable varName. If varName does not exist, it is
given a value equal to the concatenation of all the value
arguments. If varName indicate an element that does not
exist of an array that has a default value set, the concatenation
of the default value and all the value arguments will be
stored in the array element. The result of this command is the new
value stored in variable varName. This command provides an
efficient way to build up long variables incrementally. For
example, “append a $b” is much more efficient than “set a
$a$b” if $a is long.
Building a string of comma-separated numbers piecemeal using a
loop.
set var 0
for {set i 1} {$i<=10} {incr i} {
append var "," $i
}
puts $var
# Prints 0,1,2,3,4,5,6,7,8,9,10
concat, lappend
append, variable
Copyright © 1993 The Regents of the University of
California.
Copyright © 1994-1996 Sun Microsystems, Inc.