bionic (3) lsearch.3tcl.gz

Provided by: tcl8.5-doc_8.5.19-4_all bug

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