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append(3tcl) Tcl Built-In Commands append(3tcl) 





NAME


append - Append to variable






SYNOPSIS


append varName ?value value value ...?








DESCRIPTION


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.






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