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diff --git a/doc/lsearch.n b/doc/lsearch.n new file mode 100644 index 0000000..c2644b8 --- /dev/null +++ b/doc/lsearch.n @@ -0,0 +1,220 @@ +'\" +'\" Copyright (c) 1993 The Regents of the University of California. +'\" Copyright (c) 1994-1996 Sun Microsystems, Inc. +'\" Copyright (c) 2001 Kevin B. Kenny <kennykb@acm.org>. 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. +'\" +.TH lsearch n 8.6 Tcl "Tcl Built-In Commands" +.so man.macros +.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 +indicates how the elements of the list are to be matched against +\fIpattern\fR and must have one of the values below: +.SS "MATCHING STYLE OPTIONS" +.PP +If all matching style options are omitted, the default matching style +is \fB\-glob\fR. If more than one matching style is specified, the +last matching style given takes precedence. +.TP +\fB\-exact\fR +. +\fIPattern\fR is a literal string that is compared for exact equality +against each list element. +.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 mutually exclusive with \fB\-glob\fR and \fB\-regexp\fR, and +is treated exactly like \fB\-exact\fR when either \fB\-all\fR or +\fB\-not\fR are specified. +.SS "GENERAL MODIFIER OPTIONS" +.PP +These options may be given with all matching styles. +.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.) 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 \fIlist\fR. +.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. +The interpretation of the \fIindex\fR value is the same as +for the command \fBstring index\fR, supporting simple index +arithmetic and indices relative to the end of the list. +.SS "CONTENTS DESCRIPTION OPTIONS" +.PP +These options describe how to interpret the items in the list being +searched. They are only meaningful when used with the \fB\-exact\fR +and \fB\-sorted\fR options. If more than one is specified, the last +one 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 (see \fBlsort\fR for a fuller description). Note that this +only makes a meaningful difference from the \fB\-ascii\fR option when +the \fB\-sorted\fR option is given, because values are only +dictionary-equal when exactly equal. +.TP +\fB\-integer\fR +. +The list elements are to be compared as integers. +.TP +\fB\-nocase\fR +. +Causes comparisons to be handled in a case-insensitive manner. Has no +effect if combined with the \fB\-dictionary\fR, \fB\-integer\fR, or +\fB\-real\fR options. +.TP +\fB\-real\fR +. +The list elements are to be compared as floating-point values. +.SS "SORTED LIST OPTIONS" +.PP +These options (only meaningful with the \fB\-sorted\fR option) specify +how the list is sorted. If more than one is given, the last one takes +precedence. The default option is \fB\-increasing\fR. +.TP +\fB\-decreasing\fR +. +The list elements are sorted in decreasing order. This option is only +meaningful when used with \fB\-sorted\fR. +.TP +\fB\-increasing\fR +. +The list elements are sorted in increasing order. This option is only +meaningful when used with \fB\-sorted\fR. +.TP +\fB\-bisect\fR +.VS 8.6 +Inexact search when the list elements are in sorted order. For an increasing +list the last index where the element is less than or equal to the pattern +is returned. For a decreasing list the last index where the element is greater +than or equal to the pattern is returned. If the pattern is before the first +element or the list is empty, -1 is returned. +This option implies \fB\-sorted\fR and cannot be used with either \fB\-all\fR +or \fB\-not\fR. +.VE 8.6 +.SS "NESTED LIST OPTIONS" +.PP +These options are used to search lists of lists. They may be used +with any other options. +.TP +\fB\-index\fR\0\fIindexList\fR +. +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. +.TP +\fB\-subindices\fR +. +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. +.SH EXAMPLES +.PP +Basic searching: +.PP +.CS +\fBlsearch\fR {a b c d e} c + \fI\(-> 2\fR +\fBlsearch\fR -all {a b c a b c} c + \fI\(-> 2 5\fR +.CE +.PP +Using \fBlsearch\fR to filter lists: +.PP +.CS +\fBlsearch\fR -inline {a20 b35 c47} b* + \fI\(-> b35\fR +\fBlsearch\fR -inline -not {a20 b35 c47} b* + \fI\(-> a20\fR +\fBlsearch\fR -all -inline -not {a20 b35 c47} b* + \fI\(-> a20 c47\fR +\fBlsearch\fR -all -not {a20 b35 c47} b* + \fI\(-> 0 2\fR +.CE +.PP +This can even do a +.QW set-like +removal operation: +.PP +.CS +\fBlsearch\fR -all -inline -not -exact {a b c a d e a f g a} a + \fI\(-> b c d e f g\fR +.CE +.PP +Searching may start part-way through the list: +.PP +.CS +\fBlsearch\fR -start 3 {a b c a b c} c + \fI\(-> 5\fR +.CE +.PP +It is also possible to search inside elements: +.PP +.CS +\fBlsearch\fR -index 1 -all -inline {{a abc} {b bcd} {c cde}} *bc* + \fI\(-> {a abc} {b bcd}\fR +.CE +.SH "SEE ALSO" +foreach(n), list(n), lappend(n), lindex(n), linsert(n), llength(n), +lset(n), lsort(n), lrange(n), lreplace(n), +string(n) +.SH KEYWORDS +binary search, linear search, +list, match, pattern, regular expression, search, string +'\" Local Variables: +'\" mode: nroff +'\" End: |