Improve the clarity of the lsearch manpage. Thanks to Peter Spjuth!

2 files changed, 96 insertions, 74 deletions

diff --git a/ChangeLog b/ChangeLog
index e2e0d2e..e162aee 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
 2004-05-18  Donal K. Fellows  <donal.k.fellows@man.ac.uk>
 
+	* doc/lsearch.n: Improve clarity (based on [Patch 955361] by Peter
+	Spjuth)
+
 	* tools/man2help2.tcl (macro,SHmacro): Added support for
 	subsection (.SS) header macros.
 
diff --git a/doc/lsearch.n b/doc/lsearch.n
index f723236..9b42447 100644
--- a/doc/lsearch.n
+++ b/doc/lsearch.n
@@ -8,7 +8,7 @@
 '\" 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 $
+'\" RCS: @(#) $Id: lsearch.n,v 1.18 2004/05/18 12:54:35 dkf Exp $
 '\" 
 .so man.macros
 .TH lsearch n 8.5 Tcl "Tcl Built-In Commands"
@@ -28,25 +28,11 @@ 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 it must have one of the following values:
-.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\-ascii\fR
-The list elements are to be examined as Unicode strings (the name is
-for backward-compatability reasons.)  This option is only meaningful
-when used with \fB\-exact\fR or \fB\-sorted\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\-dictionary\fR
-The list elements are to be compared using dictionary-style
-comparisons.  This option is only meaningful when used with
-\fB\-exact\fR or \fB\-sorted\fR.
+\fIpattern\fR and must have one of the values below:
+.SS "MATCHING STYLE OPTIONS"
+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
 The list element must contain exactly the same string as \fIpattern\fR.
@@ -55,35 +41,6 @@ The list element must contain exactly the same string as \fIpattern\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\-increasing\fR
-The list elements are sorted in increasing order.  This option is only
-meaningful when used with \fB\-sorted\fR.
-.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\-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\-integer\fR
-The list elements are to be compared as integers.  This option is only
-meaningful when used with \fB\-exact\fR or \fB\-sorted\fR.
-.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\-real\fR
-The list elements are to be compared as floating-point values.  This
-option is only meaningful when used with \fB\-exact\fR or \fB\-sorted\fR.
-.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
@@ -95,52 +52,114 @@ The list elements are in sorted order.  If this option is specified,
 \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 is specified.
+is treated exactly like \fB-exact\fR when either \fB\-all\fR or
+\fB\-not\fR are specified.
+.SS "GENERAL MODIFIER OPTIONS"
+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.)
+.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.
+.SS "CONTENTS DESCRIPTION OPTIONS"
+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\-subindices\fR
+\fB\-ascii\fR
+The list elements are to be examined as Unicode strings (the name is
+for backward-compatability 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.
+.SS "SORTED LIST OPTIONS"
+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.
+.SS "NESTED LIST OPTIONS"
 .VS 8.5
+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
 \fI\-index\fR is also specified, and is just a convenience short-cut.
 .VE 8.5
-.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.  If more than one of \fB\-ascii\fR, \fB\-dictionary\fR,
-\fB\-integer\fR and \fB\-real\fR is specified, the option specified
-last takes precedence.  If more than one of \fB\-increasing\fR and
-\fB\-decreasing\fR is specified, the option specified last takes
-precedence.
-
 .SH EXAMPLES
+Basic searching:
 .CS
-lsearch {a b c d e} c => 2
-lsearch -all {a b c a b c} c => 2 5
+lsearch {a b c d e} c
+      => 2
+lsearch -all {a b c a b c} c
+      => 2 5
+.CE
 
-\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
+Using \fBlsearch\fR to filter lists:
+.CS
+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
+.CE
+This can even do a "set-like" removal operation:
+.CS
 lsearch -all -inline -not -exact {a b c a d e a f g a} a
       => b c d e f g
+.CE
 
-\fI# Non-start based searches\fR
-lsearch -start 3 {a b c a b c} c => 5
+Searching may start part-way through the list:
+.CS
+lsearch -start 3 {a b c a b c} c
+      => 5
+.CE
 
-\fI# Searching inside elements\fR
-lsearch -index 1 -all {{a abc} {b bcd} {c cde}} *bc* => {a abc} {b bcd}
+It is also possible to search inside elements:
+.CS
+lsearch -index 1 -all {{a abc} {b bcd} {c cde}} *bc*
+      => {a abc} {b bcd}
 .CE
 
 .SH "SEE ALSO"