NAME
       lsort - Sort the elements of a list

SYNOPSIS
       lsort ?options? list


DESCRIPTION
       This  command  sorts the elements of list, returning a new
       list in sorted order.  The  implementation  of  the  lsort
       command  uses  the  merge-sort algorithm which is a stable
       sort that has O(n log n) performance characteristics.

       By default ASCII sorting is used with the result  returned
       in  increasing  order.   However,  any  of  the  following
       options may  be  specified  before  list  to  control  the
       sorting process (unique abbreviations are accepted):

       -ascii              Use   string   comparison  with  ASCII
                           collation order.  This is the default.

       -dictionary         Use dictionary-style comparison.  This
                           is the same as -ascii except (a)  case
                           is ignored except as a tie-breaker and
                           (b) if two  strings  contain  embedded
                           numbers,   the   numbers   compare  as
                           integers,   not    characters.     For
                           example,  in  -dictionary mode, bigBoy
                           sorts between bigbang and bigboy,  and
                           x10y sorts between x9y and x11y.

       -integer            Convert  list elements to integers and
                           use integer comparison.

       -real               Convert  list  elements  to  floating-
                           point    values   and   use   floating
                           comparison.

       -command command    Use command as a  comparison  command.
                           To  compare  two  elements, evaluate a
                           Tcl script consisting of command  with
                           the    two    elements   appended   as
                           additional  arguments.    The   script
                           should  return  an  integer less than,
                           equal to, or greater than zero if  the
                           first element is to be considered less
                           than, equal to, or  greater  than  the
                           second, respectively.

       -increasing         Sort  the  list  in  increasing  order
                           (``smallest'' items first).   This  is
                           the default.

       -decreasing         Sort  the  list  in  decreasing  order
                           (``largest'' items first).

       -index index        If this option is specified,  each  of
                           the  elements of list must itself be a
                           proper  Tcl   sublist.    Instead   of
                           sorting based on whole sublists, lsort
                           will extract the index'th element from
                           each  sublist  and  sort  based on the
                           given element.   The  keyword  end  is
                           allowed  for  the index to sort on the
                           last sublist element. For example,
                                  lsort -integer -index 1 {{First 24} {Second 18} {Third 30}}
                           returns {Second 18} {First 24}  {Third
                           30}.    This   option   is  much  more
                           efficient  than  using   -command   to
                           achieve the same effect.

       -unique             If this option is specified, then only
                           the last  set  of  duplicate  elements
                           found  in  the  list will be retained.
                           Note that  duplicates  are  determined
                           relative to the comparison used in the
                           sort.  Thus if -index 0 is used, {1 a}
                           and   {1   b}   would   be  considered
                           duplicates   and   only   the   second
                           element, {1 b}, would be retained.


KEYWORDS
