Provided by: tcl8.6-doc_8.6.1-4ubuntu1_all bug


       unset - Delete variables


       unset ?-nocomplain? ?--? ?name name name ...?


       This  command  removes  one or more variables.  Each name is a variable name, specified in
       any of the ways acceptable to the set command.  If a name refers to an element of an array
       then  that element is removed without affecting the rest of the array.  If a name consists
       of an array name with no parenthesized index, then the entire array is deleted.  The unset
       command  returns  an  empty  string  as  result.  If -nocomplain is specified as the first
       argument, any possible errors are suppressed.  The option may not be abbreviated, in order
       to  disambiguate  it from possible variable names.  The option -- indicates the end of the
       options, and should be used if you wish to remove a variable with the same name as any  of
       the  options.   If an error occurs during variable deletion, any variables after the named
       one causing the error are not deleted.  An error can occur when the  named  variable  does
       not  exist,  or  the  name refers to an array element but the variable is a scalar, or the
       name refers to a variable in a non-existent namespace.


       Create an array containing a mapping from some numbers to their  squares  and  remove  the
       array elements for non-prime numbers:

              array set squares {
                  1 1    6 36
                  2 4    7 49
                  3 9    8 64
                  4 16   9 81
                  5 25  10 100

              puts "The squares are:"
              parray squares

              unset squares(1) squares(4) squares(6)
              unset squares(8) squares(9) squares(10)

              puts "The prime squares are:"
              parray squares


       set(3tcl), trace(3tcl), upvar(3tcl)


       remove, variable