append(3tcl) Tcl Built-In Commands append(3tcl)
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NAME
append - Append to variable
SYNOPSIS
append varName ?value value value ...?
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DESCRIPTION
Append all of the value arguments to the current value of variable var-
Name. If varName does not exist, it is given a value equal to the con-
catenation of all the value arguments. The result of this command is
the new value stored in variable varName. This command provides an ef-
ficient way to build up long variables incrementally. For example,
“append a $b” is much more efficient than “set a $a$b” if $a is long.
EXAMPLE
Building a string of comma-separated numbers piecemeal using a loop.
set var 0
for {set i 1} {$i<=10} {incr i} {
append var "," $i
}
puts $var
# Prints 0,1,2,3,4,5,6,7,8,9,10
SEE ALSO
concat(3tcl), lappend(3tcl)
KEYWORDS
append, variable
Tcl append(3tcl)
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