NAME
       for - ``For'' loop

SYNOPSIS
       for start test next body


DESCRIPTION
       For  is  a  looping command, similar in structure to the C
       for statement.  The start, next, and body  arguments  must
       be  Tcl command strings, and test is an expression string.
       The for command  first  invokes  the  Tcl  interpreter  to
       execute  start.   Then  it repeatedly evaluates test as an
       expression; if the result is non-zero it invokes  the  Tcl
       interpreter  on  body, then invokes the Tcl interpreter on
       next, then repeats the loop.  The command terminates  when
       test  evaluates  to  0.   If a continue command is invoked
       within body then any remaining  commands  in  the  current
       execution  of  body  are  skipped; processing continues by
       invoking the Tcl  interpreter  on  next,  then  evaluating
       test,  and  so  on.   If a break command is invoked within
       body  or  next,  then  the   for   command   will   return
       immediately.   The  operation  of  break  and continue are
       similar to the corresponding statements in C.  For returns
       an empty string.

       Note: test should almost always be enclosed in braces.  If
       not, variable substitutions will be made  before  the  for
       command   starts  executing,  which  means  that  variable
       changes made by the loop body will not  be  considered  in
       the  expression.   This is likely to result in an infinite
       loop.   If  test   is   enclosed   in   braces,   variable
       substitutions   are   delayed   until  the  expression  is
       evaluated (before each loop iteration), so changes in  the
       variables  will  be  visible.   For  an  example,  try the
       following script with and without the braces around $x<10:
              for {set x 0} {$x<10} {incr x} {
                puts "x is $x"
              }


KEYWORDS
