lappend - Append list elements onto a variable

       This  command  treats  the variable given by varName as a list and appends each of the value arguments to
       that list as a separate element, with spaces between elements.  If varName does not exist, it is  created
       as a list with elements given by the value arguments.  If varName indicate an element that does not exist 2
       of  an array that has a default value set, list that is comprised of the default value with all the value 2
       arguments appended as elements will be stored in the array element.  Lappend is similar to append  except
       that  the  values are appended as list elements rather than raw text.  This command provides a relatively
       efficient way to build up large lists.  For example, “lappenda$b” is much more efficient  than  “seta[concat$a[list$b]]” when $a is long.

       Using lappend to build up a list of numbers.

              % set var 1
              1
              % lappend var 2
              1 2
              % lappend var 3 4 5
              1 2 3 4 5

       append, element, list, variable

Tcl                                                                                                lappend(3tcl)

       lappend - Append list elements onto a variable

list(3tcl),   lassign(3tcl),   ledit(3tcl),   lindex(3tcl),   linsert(3tcl),  llength(3tcl),  lmap(3tcl),
       lpop(3tcl), lrange(3tcl), lremove(3tcl), lrepeat(3tcl),  lreplace(3tcl),  lreverse(3tcl),  lsearch(3tcl),
       lseq(3tcl), lset(3tcl), lsort(3tcl)

lappendvarName ?valuevaluevalue...?
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