# word.tcl --## This file defines various procedures for computing word boundaries# in strings.  This file is primarily needed so Tk text and entry# widgets behave properly for different platforms.## Copyright (c) 1996 by Sun Microsystems, Inc.## See the file "license.terms" for information on usage and redistribution# of this file, and for a DISCLAIMER OF ALL WARRANTIES.# # RCS: @(#) $Id: word.tcl,v 1.3 1998/09/14 18:40:03 stanton Exp $# # See the file "license.terms" for information on usage and redistribution# of this file, and for a DISCLAIMER OF ALL WARRANTIES.## The following variables are used to determine which characters are# interpreted as white space.  if {$tcl_platform(platform) == "windows"} {    # Windows style - any but space, tab, or newline    set tcl_wordchars "\[^ \t\n\]"    set tcl_nonwordchars "\[ \t\n\]"} else {    # Motif style - any number, letter, or underscore    set tcl_wordchars {[a-zA-Z0-9_]}    set tcl_nonwordchars {[^a-zA-Z0-9_]}}# tcl_wordBreakAfter --## This procedure returns the index of the first word boundary# after the starting point in the given string, or -1 if there# are no more boundaries in the given string.  The index returned refers# to the first character of the pair that comprises a boundary.## Arguments:# str -		String to search.# start -	Index into string specifying starting point.proc tcl_wordBreakAfter {str start} {    global tcl_nonwordchars tcl_wordchars    set str [string range $str $start end]    if {[regexp -indices "$tcl_wordchars$tcl_nonwordchars|$tcl_nonwordchars$tcl_wordchars" $str result]} {	return [expr {[lindex $result 1] + $start}]    }    return -1}# tcl_wordBreakBefore --## This procedure returns the index of the first word boundary# before the starting point in the given string, or -1 if there# are no more boundaries in the given string.  The index returned# refers to the second character of the pair that comprises a boundary.## Arguments:# str -		String to search.# start -	Index into string specifying starting point.proc tcl_wordBreakBefore {str start} {    global tcl_nonwordchars tcl_wordchars    if {[string compare $start end] == 0} {	set start [string length $str]    }    if {[regexp -indices "^.*($tcl_wordchars$tcl_nonwordchars|$tcl_nonwordchars$tcl_wordchars)" [string range $str 0 $start] result]} {	return [lindex $result 1]    }    return -1}# tcl_endOfWord --## This procedure returns the index of the first end-of-word location# after a starting index in the given string.  An end-of-word location# is defined to be the first whitespace character following the first# non-whitespace character after the starting point.  Returns -1 if# there are no more words after the starting point.## Arguments:# str -		String to search.# start -	Index into string specifying starting point.proc tcl_endOfWord {str start} {    global tcl_nonwordchars tcl_wordchars    if {[regexp -indices "$tcl_nonwordchars*$tcl_wordchars+$tcl_nonwordchars" \	    [string range $str $start end] result]} {	return [expr {[lindex $result 1] + $start}]    }    return -1}# tcl_startOfNextWord --## This procedure returns the index of the first start-of-word location# after a starting index in the given string.  A start-of-word# location is defined to be a non-whitespace character following a# whitespace character.  Returns -1 if there are no more start-of-word# locations after the starting point.## Arguments:# str -		String to search.# start -	Index into string specifying starting point.proc tcl_startOfNextWord {str start} {    global tcl_nonwordchars tcl_wordchars    if {[regexp -indices "$tcl_wordchars*$tcl_nonwordchars+$tcl_wordchars" \	    [string range $str $start end] result]} {	return [expr {[lindex $result 1] + $start}]    }    return -1}# tcl_startOfPreviousWord --## This procedure returns the index of the first start-of-word location# before a starting index in the given string.## Arguments:# str -		String to search.# start -	Index into string specifying starting point.proc tcl_startOfPreviousWord {str start} {    global tcl_nonwordchars tcl_wordchars    if {[string compare $start end] == 0} {	set start [string length $str]    }    if {[regexp -indices \	    "$tcl_nonwordchars*($tcl_wordchars+)$tcl_nonwordchars*\$" \	    [string range $str 0 [expr {$start - 1}]] result word]} {	return [lindex $word 0]    }    return -1}