Attachment "lsearch.n" to
ticket [955361ffff]
added by
pspjuth
2004-05-18 00:24:47.
'\" -*- nroff -*-
'\"
'\" Copyright (c) 1993 The Regents of the University of California.
'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
'\" Copyright (c) 2001 Kevin B. Kenny. All rights reserved.
'\" Copyright (c) 2003-2004 Donal K. Fellows.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\"
'\" RCS: @(#) $Id: lsearch.n,v 1.17 2004/04/28 10:28:00 dkf Exp $
'\"
.so man.macros
.TH lsearch n 8.5 Tcl "Tcl Built-In Commands"
.BS
'\" Note: do not modify the .SH NAME line immediately below!
.SH NAME
lsearch \- See if a list contains a particular element
.SH SYNOPSIS
\fBlsearch \fR?\fIoptions\fR? \fIlist pattern\fR
.BE
.SH DESCRIPTION
.PP
This command searches the elements of \fIlist\fR to see if one
of them matches \fIpattern\fR. If so, the command returns the index
of the first matching element
(unless the options \fB\-all\fR or \fB\-inline\fR are specified.)
If not, the command returns \fB\-1\fR. The \fIoption\fR arguments
indicate how the elements of the list are to be matched against
\fIpattern\fR and it must have one of the values below.
.SH "Matching style options"
.PP
If \fIoption\fR is omitted then it defaults to \fB\-glob\fR. If more
than one of \fB\-exact\fR, \fB\-glob\fR, \fB\-regexp\fR, and
\fB\-sorted\fR is specified, whichever option is specified last takes
precedence.
.TP
\fB\-exact\fR
The list element must contain exactly the same string as \fIpattern\fR.
.TP
\fB\-glob\fR
\fIPattern\fR is a glob-style pattern which is matched against each list
element using the same rules as the \fBstring match\fR command.
.TP
\fB\-regexp\fR
\fIPattern\fR is treated as a regular expression and matched against
each list element using the rules described in the \fBre_syntax\fR
reference page.
.TP
\fB\-sorted\fR
The list elements are in sorted order. If this option is specified,
\fBlsearch\fR will use a more efficient searching algorithm to search
\fIlist\fR. If no other options are specified, \fIlist\fR is assumed
to be sorted in increasing order, and to contain ASCII strings. This
option is treated exactly like \fB-exact\fR when either \fB\-all\fR, or
\fB\-not\fR is specified.
.SH "Misc options"
.TP
\fB\-all\fR
Changes the result to be the list of all matching indices (or all
matching values if \fB\-inline\fR is specified as well.)
.TP
\fB\-inline\fR
The matching value is returned instead of its index (or an empty
string if no value matches.) If \fB\-all\fR is also specified, then
the result of the command is the list of all values that matched.
.TP
\fB\-not\fR
This negates the sense of the match, returning the index of the first
non-matching value in the list.
.TP
\fB\-start\fR\0\fIindex\fR
The list is searched starting at position \fIindex\fR. If \fIindex\fR
has the value \fBend\fR, it refers to the last element in the list,
and \fBend\-\fIinteger\fR refers to the last element in the list minus
the specified integer offset.
.SH "Contents options"
.PP
These options tell how to interpret list elements. They are only
meaningful when used with \fB\-exact\fR or \fB\-sorted\fR. If
more than one of them is specified, the option specified last
takes precedence. The default is \fB-ascii\fR.
.TP
\fB\-ascii\fR
The list elements are to be examined as Unicode strings (the name is
for backward-compatibility reasons.)
.TP
\fB\-dictionary\fR
The list elements are to be compared using dictionary-style
comparisons.
.TP
\fB\-integer\fR
The list elements are to be compared as integers.
.TP
\fB\-real\fR
The list elements are to be compared as floating-point values.
.SH "Sorted list options"
.PP
These options are only meaningful when used with \fB\-sorted\fR. If
more than one of them is specified, the option specified last takes
precedence. The default is \fB-increasing\fR.
.TP
\fB\-decreasing\fR
The list elements are sorted in decreasing order.
.TP
\fB\-increasing\fR
The list elements are sorted in increasing order.
.SH "Nested list options"
.TP
\fB\-index\fR\0\fIindexList\fR
.VS 8.5
This option is designed for use when searching within nested lists.
The \fIindexList\fR argument gives a path of indices (much as might be
used with the \fBlindex\fR or \fBlset\fR commands) within each element
to allow the location of the term being matched against.
.VE 8.5
.TP
\fB\-subindices\fR
.VS 8.5
If this option is given, the index result from this command (or every
index result when \fB\-all\fR is also specified) will be a complete
path (suitable for use with \fBlindex\fR or \fBlset\fR) within the
overall list to the term found. This option has no effect unless the
\fB\-index\fR is also specified, and is just a convenience short-cut.
.VE 8.5
.PP
.SH EXAMPLES
.CS
lsearch {a b c d e} c => 2
lsearch -all {a b c a b c} c => 2 5
\fI# Filtering examples\fR
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
\fI# Simple set removal\fR
lsearch -all -inline -not -exact {a b c a d e a f g a} a
=> b c d e f g
\fI# Non-start based searches\fR
lsearch -start 3 {a b c a b c} c => 5
\fI# Searching inside elements\fR
lsearch -index 1 -all {{a abc} {b bcd} {c cde}} *bc* => {a abc} {b bcd}
.CE
.SH "SEE ALSO"
foreach(n), list(n), lappend(n), lindex(n), linsert(n), llength(n),
lset(n), lsort(n), lrange(n), lreplace(n)
.SH KEYWORDS
list, match, pattern, regular expression, search, string
