lsearch(3tcl)


NAME

   lsearch - See if a list contains a particular element

SYNOPSIS

   lsearch ?options? list pattern
______________________________________________________________________________

DESCRIPTION

   This  command  searches  the  elements  of  list  to see if one of them
   matches pattern.  If so, the command returns the  index  of  the  first
   matching  element  (unless  the options -all or -inline are specified.)
   If not, the command returns -1.  The option arguments indicates how the
   elements  of  the  list are to be matched against pattern and must have
   one of the values below:

   MATCHING STYLE OPTIONS
   If all matching style options are omitted, the default  matching  style
   is  -glob.   If  more  than  one  matching style is specified, the last
   matching style given takes precedence.

   -exact Pattern is a literal string that is compared for exact  equality
          against each list element.

   -glob  Pattern  is  a  glob-style pattern which is matched against each
          list element using the same rules as the string match command.

   -regexp
          Pattern is treated as a regular expression and  matched  against
          each  list  element  using  the rules described in the re_syntax
          reference page.

   -sorted
          The list elements are  in  sorted  order.   If  this  option  is
          specified, lsearch will use a more efficient searching algorithm
          to search list.  If no other  options  are  specified,  list  is
          assumed  to  be sorted in increasing order, and to contain ASCII
          strings.  This option  is  mutually  exclusive  with  -glob  and
          -regexp,  and is treated exactly like -exact when either -all or
          -not are specified.

   GENERAL MODIFIER OPTIONS
   These options may be given with all matching styles.

   -all   Changes the result to be the list of all  matching  indices  (or
          all matching values if -inline is specified as well.) If indices
          are returned, the indices will be in numeric  order.  If  values
          are returned, the order of the values will be the order of those
          values within the input list.

   -inline
          The matching value is returned instead of its index (or an empty
          string  if  no  value matches.)  If -all is also specified, then
          the result of the  command  is  the  list  of  all  values  that
          matched.

   -not   This  negates the sense of the match, returning the index of the
          first non-matching value in the list.

   -start index
          The  list  is  searched  starting  at   position   index.    The 
          interpretation of the index value is the same as for the command 
          string index, supporting simple  index  arithmetic  and  indices 
          relative to the end of the list.

   CONTENTS DESCRIPTION OPTIONS
   These  options  describe  how  to interpret the items in the list being
   searched.  They are only meaningful  when  used  with  the  -exact  and
   -sorted  options.   If  more  than one is specified, the last one takes
   precedence.  The default is -ascii.

   -ascii The list elements are to be examined  as  Unicode  strings  (the
          name is for backward-compatibility reasons.)

   -dictionary
          The  list  elements  are  to  be compared using dictionary-style
          comparisons (see lsort for a fuller description). Note that this
          only  makes  a meaningful difference from the -ascii option when
          the -sorted option is given, because values are only dictionary-
          equal when exactly equal.

   -integer
          The list elements are to be compared as integers.                

   -nocase                                                                 
          Causes  comparisons  to be handled in a case-insensitive manner. 
          Has no effect if combined with  the  -dictionary,  -integer,  or 
          -real options.

   -real  The list elements are to be compared as floating-point values.

   SORTED LIST OPTIONS
   These options (only meaningful with the -sorted option) specify how the
   list is sorted.  If  more  than  one  is  given,  the  last  one  takes
   precedence.  The default option is -increasing.

   -decreasing
          The  list  elements are sorted in decreasing order.  This option
          is only meaningful when used with -sorted.

   -increasing
          The list elements are sorted in increasing order.   This  option
          is only meaningful when used with -sorted.

   NESTED LIST OPTIONS
   These options are used to search lists of lists.  They may be used with 
   any other options.                                                      

   -index indexList                                                        
          This option is designed for use  when  searching  within  nested 
          lists.   The indexList argument gives a path of indices (much as 
          might be used with the lindex  or  lset  commands)  within  each 
          element to allow the location of the term being matched against. 

   -subindices                                                             
          If  this option is given, the index result from this command (or 
          every index result when  -all  is  also  specified)  will  be  a 
          complete  path (suitable for use with lindex or lset) within the 
          overall list to the term  found.   This  option  has  no  effect 
          unless  the  -index is also specified, and is just a convenience 
          short-cut.

EXAMPLES

   Basic searching:
          lsearch {a b c d e} c
                 2
          lsearch -all {a b c a b c} c
                 2 5

   Using lsearch to filter lists:
          lsearch -inline {a20 b35 c47} b*
                 b35
          lsearch -inline -not {a20 b35 c47} b*
                 a20
          lsearch -all -inline -not {a20 b35 c47} b*
                 a20 c47
          lsearch -all -not {a20 b35 c47} b*
                 0 2

   This can even do a "set-like" removal operation:
          lsearch -all -inline -not -exact {a b c a d e a f g a} a
                 b c d e f g

   Searching may start part-way through the list:
          lsearch -start 3 {a b c a b c} c
                 5

   It is also possible to search inside elements:
          lsearch -index 1 -all -inline {{a abc} {b bcd} {c cde}} *bc*
                 {a abc} {b bcd}

SEE ALSO

   foreach(3tcl), list(3tcl), lappend(3tcl), lindex(3tcl),  linsert(3tcl),
   llength(3tcl),  lset(3tcl),  lsort(3tcl), lrange(3tcl), lreplace(3tcl), 
   string(3tcl)

KEYWORDS

   list, match, pattern, regular expression, search, string





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