NAME
  foreach - Iterate over all elements in one or more lists

SYNOPSIS
  foreach varname list body
  foreach varlist1 list1 ?varlist2 list2 ...? body

DESCRIPTION
  The foreach command implements a loop where the loop variable(s) take on
  values from one or more lists. In the simplest case there is one loop
  variable, varname, and one list, list, that is a list of values to
  assign to varname. The body argument is a Tcl script. For each element
  of list (in order from first to last), foreach assigns the contents of
  the element to varname as if the lindex command had been used to extract
  the element, then calls the Tcl interpreter to execute body.

  In the general case there can be more than one value list (e.g., list1
  and list2), and each value list can be associated with a list of loop
  variables (e.g., varlist1 and varlist2). During each iteration of the
  loop the variables of each varlist are assigned consecutive values from
  the corresponding list. Values in each list are used in order from first
  to last, and each value is used exactly once. The total number of loop
  iterations is large enough to use up all the values from all the value
  lists. If a value list does not contain enough elements for each of its
  loop variables in each iteration, empty values are used for the missing
  elements.

  The break and continue statements may be invoked inside body, with the
  same effect as in the for command. Foreach returns an empty string.

EXAMPLES
  The following loop uses i and j as loop variables to iterate over pairs
  of elements of a single list.

    set x {}
    foreach {i j} {a b c d e f} {
      lappend x $j $i
    }
    # The value of x is "b a d c f e"
    # There are 3 iterations of the loop.

  The next loop uses i and j to iterate over two lists in parallel.

    set x {}
    foreach i {a b c} j {d e f g} {
      lappend x $i $j
    }
    # The value of x is "a d b e c f {} g"
    # There are 4 iterations of the loop.

  The two forms are combined in the following example.

    set x {}
    foreach i {a b c} {j k} {d e f g} {
      lappend x $i $j $k
    }
    # The value of x is "a d e b f g c {} {}"
    # There are 3 iterations of the loop.

  % set l [list A B C D E F]
  A B C D E F
  
  % foreach el $l {
      puts $el
    }
  A
  B
  C
  D
  E
  F

SEE ALSO
  break continue for while