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.