--- /dev/null
+'\"
+'\" Copyright (c) 1994 The Regents of the University of California.
+'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
+'\" Copyright (c) 1998-1999 Scriptics Corporation
+'\"
+'\" See the file "license.terms" for information on usage and redistribution
+'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+'\"
+.TH Tcl_RegExpMatch 3 8.1 Tcl "Tcl Library Procedures"
+.\" The -*- nroff -*- definitions below are for supplemental macros used
+.\" in Tcl/Tk manual entries.
+.\"
+.\" .AP type name in/out ?indent?
+.\" Start paragraph describing an argument to a library procedure.
+.\" type is type of argument (int, etc.), in/out is either "in", "out",
+.\" or "in/out" to describe whether procedure reads or modifies arg,
+.\" and indent is equivalent to second arg of .IP (shouldn't ever be
+.\" needed; use .AS below instead)
+.\"
+.\" .AS ?type? ?name?
+.\" Give maximum sizes of arguments for setting tab stops. Type and
+.\" name are examples of largest possible arguments that will be passed
+.\" to .AP later. If args are omitted, default tab stops are used.
+.\"
+.\" .BS
+.\" Start box enclosure. From here until next .BE, everything will be
+.\" enclosed in one large box.
+.\"
+.\" .BE
+.\" End of box enclosure.
+.\"
+.\" .CS
+.\" Begin code excerpt.
+.\"
+.\" .CE
+.\" End code excerpt.
+.\"
+.\" .VS ?version? ?br?
+.\" Begin vertical sidebar, for use in marking newly-changed parts
+.\" of man pages. The first argument is ignored and used for recording
+.\" the version when the .VS was added, so that the sidebars can be
+.\" found and removed when they reach a certain age. If another argument
+.\" is present, then a line break is forced before starting the sidebar.
+.\"
+.\" .VE
+.\" End of vertical sidebar.
+.\"
+.\" .DS
+.\" Begin an indented unfilled display.
+.\"
+.\" .DE
+.\" End of indented unfilled display.
+.\"
+.\" .SO ?manpage?
+.\" Start of list of standard options for a Tk widget. The manpage
+.\" argument defines where to look up the standard options; if
+.\" omitted, defaults to "options". The options follow on successive
+.\" lines, in three columns separated by tabs.
+.\"
+.\" .SE
+.\" End of list of standard options for a Tk widget.
+.\"
+.\" .OP cmdName dbName dbClass
+.\" Start of description of a specific option. cmdName gives the
+.\" option's name as specified in the class command, dbName gives
+.\" the option's name in the option database, and dbClass gives
+.\" the option's class in the option database.
+.\"
+.\" .UL arg1 arg2
+.\" Print arg1 underlined, then print arg2 normally.
+.\"
+.\" .QW arg1 ?arg2?
+.\" Print arg1 in quotes, then arg2 normally (for trailing punctuation).
+.\"
+.\" .PQ arg1 ?arg2?
+.\" Print an open parenthesis, arg1 in quotes, then arg2 normally
+.\" (for trailing punctuation) and then a closing parenthesis.
+.\"
+.\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
+.if t .wh -1.3i ^B
+.nr ^l \n(.l
+.ad b
+.\" # Start an argument description
+.de AP
+.ie !"\\$4"" .TP \\$4
+.el \{\
+. ie !"\\$2"" .TP \\n()Cu
+. el .TP 15
+.\}
+.ta \\n()Au \\n()Bu
+.ie !"\\$3"" \{\
+\&\\$1 \\fI\\$2\\fP (\\$3)
+.\".b
+.\}
+.el \{\
+.br
+.ie !"\\$2"" \{\
+\&\\$1 \\fI\\$2\\fP
+.\}
+.el \{\
+\&\\fI\\$1\\fP
+.\}
+.\}
+..
+.\" # define tabbing values for .AP
+.de AS
+.nr )A 10n
+.if !"\\$1"" .nr )A \\w'\\$1'u+3n
+.nr )B \\n()Au+15n
+.\"
+.if !"\\$2"" .nr )B \\w'\\$2'u+\\n()Au+3n
+.nr )C \\n()Bu+\\w'(in/out)'u+2n
+..
+.AS Tcl_Interp Tcl_CreateInterp in/out
+.\" # BS - start boxed text
+.\" # ^y = starting y location
+.\" # ^b = 1
+.de BS
+.br
+.mk ^y
+.nr ^b 1u
+.if n .nf
+.if n .ti 0
+.if n \l'\\n(.lu\(ul'
+.if n .fi
+..
+.\" # BE - end boxed text (draw box now)
+.de BE
+.nf
+.ti 0
+.mk ^t
+.ie n \l'\\n(^lu\(ul'
+.el \{\
+.\" Draw four-sided box normally, but don't draw top of
+.\" box if the box started on an earlier page.
+.ie !\\n(^b-1 \{\
+\h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul'
+.\}
+.el \}\
+\h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul'
+.\}
+.\}
+.fi
+.br
+.nr ^b 0
+..
+.\" # VS - start vertical sidebar
+.\" # ^Y = starting y location
+.\" # ^v = 1 (for troff; for nroff this doesn't matter)
+.de VS
+.if !"\\$2"" .br
+.mk ^Y
+.ie n 'mc \s12\(br\s0
+.el .nr ^v 1u
+..
+.\" # VE - end of vertical sidebar
+.de VE
+.ie n 'mc
+.el \{\
+.ev 2
+.nf
+.ti 0
+.mk ^t
+\h'|\\n(^lu+3n'\L'|\\n(^Yu-1v\(bv'\v'\\n(^tu+1v-\\n(^Yu'\h'-|\\n(^lu+3n'
+.sp -1
+.fi
+.ev
+.\}
+.nr ^v 0
+..
+.\" # Special macro to handle page bottom: finish off current
+.\" # box/sidebar if in box/sidebar mode, then invoked standard
+.\" # page bottom macro.
+.de ^B
+.ev 2
+'ti 0
+'nf
+.mk ^t
+.if \\n(^b \{\
+.\" Draw three-sided box if this is the box's first page,
+.\" draw two sides but no top otherwise.
+.ie !\\n(^b-1 \h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c
+.el \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c
+.\}
+.if \\n(^v \{\
+.nr ^x \\n(^tu+1v-\\n(^Yu
+\kx\h'-\\nxu'\h'|\\n(^lu+3n'\ky\L'-\\n(^xu'\v'\\n(^xu'\h'|0u'\c
+.\}
+.bp
+'fi
+.ev
+.if \\n(^b \{\
+.mk ^y
+.nr ^b 2
+.\}
+.if \\n(^v \{\
+.mk ^Y
+.\}
+..
+.\" # DS - begin display
+.de DS
+.RS
+.nf
+.sp
+..
+.\" # DE - end display
+.de DE
+.fi
+.RE
+.sp
+..
+.\" # SO - start of list of standard options
+.de SO
+'ie '\\$1'' .ds So \\fBoptions\\fR
+'el .ds So \\fB\\$1\\fR
+.SH "STANDARD OPTIONS"
+.LP
+.nf
+.ta 5.5c 11c
+.ft B
+..
+.\" # SE - end of list of standard options
+.de SE
+.fi
+.ft R
+.LP
+See the \\*(So manual entry for details on the standard options.
+..
+.\" # OP - start of full description for a single option
+.de OP
+.LP
+.nf
+.ta 4c
+Command-Line Name: \\fB\\$1\\fR
+Database Name: \\fB\\$2\\fR
+Database Class: \\fB\\$3\\fR
+.fi
+.IP
+..
+.\" # CS - begin code excerpt
+.de CS
+.RS
+.nf
+.ta .25i .5i .75i 1i
+..
+.\" # CE - end code excerpt
+.de CE
+.fi
+.RE
+..
+.\" # UL - underline word
+.de UL
+\\$1\l'|0\(ul'\\$2
+..
+.\" # QW - apply quotation marks to word
+.de QW
+.ie '\\*(lq'"' ``\\$1''\\$2
+.\"" fix emacs highlighting
+.el \\*(lq\\$1\\*(rq\\$2
+..
+.\" # PQ - apply parens and quotation marks to word
+.de PQ
+.ie '\\*(lq'"' (``\\$1''\\$2)\\$3
+.\"" fix emacs highlighting
+.el (\\*(lq\\$1\\*(rq\\$2)\\$3
+..
+.\" # QR - quoted range
+.de QR
+.ie '\\*(lq'"' ``\\$1''\\-``\\$2''\\$3
+.\"" fix emacs highlighting
+.el \\*(lq\\$1\\*(rq\\-\\*(lq\\$2\\*(rq\\$3
+..
+.\" # MT - "empty" string
+.de MT
+.QW ""
+..
+.BS
+.SH NAME
+Tcl_RegExpMatch, Tcl_RegExpCompile, Tcl_RegExpExec, Tcl_RegExpRange, Tcl_GetRegExpFromObj, Tcl_RegExpMatchObj, Tcl_RegExpExecObj, Tcl_RegExpGetInfo \- Pattern matching with regular expressions
+.SH SYNOPSIS
+.nf
+\fB#include <tcl.h>\fR
+.sp
+int
+\fBTcl_RegExpMatchObj\fR(\fIinterp\fR, \fItextObj\fR, \fIpatObj\fR)
+.sp
+int
+\fBTcl_RegExpMatch\fR(\fIinterp\fR, \fItext\fR, \fIpattern\fR)
+.sp
+Tcl_RegExp
+\fBTcl_RegExpCompile\fR(\fIinterp\fR, \fIpattern\fR)
+.sp
+int
+\fBTcl_RegExpExec\fR(\fIinterp\fR, \fIregexp\fR, \fItext\fR, \fIstart\fR)
+.sp
+void
+\fBTcl_RegExpRange\fR(\fIregexp\fR, \fIindex\fR, \fIstartPtr\fR, \fIendPtr\fR)
+.sp
+Tcl_RegExp
+\fBTcl_GetRegExpFromObj\fR(\fIinterp\fR, \fIpatObj\fR, \fIcflags\fR)
+.sp
+int
+\fBTcl_RegExpExecObj\fR(\fIinterp\fR, \fIregexp\fR, \fItextObj\fR, \fIoffset\fR, \fInmatches\fR, \fIeflags\fR)
+.sp
+void
+\fBTcl_RegExpGetInfo\fR(\fIregexp\fR, \fIinfoPtr\fR)
+.fi
+.SH ARGUMENTS
+.AS Tcl_RegExpInfo *interp in/out
+.AP Tcl_Interp *interp in
+Tcl interpreter to use for error reporting. The interpreter may be
+NULL if no error reporting is desired.
+.AP Tcl_Obj *textObj in/out
+Refers to the value from which to get the text to search. The
+internal representation of the value may be converted to a form that
+can be efficiently searched.
+.AP Tcl_Obj *patObj in/out
+Refers to the value from which to get a regular expression. The
+compiled regular expression is cached in the value.
+.AP "const char" *text in
+Text to search for a match with a regular expression.
+.AP "const char" *pattern in
+String in the form of a regular expression pattern.
+.AP Tcl_RegExp regexp in
+Compiled regular expression. Must have been returned previously
+by \fBTcl_GetRegExpFromObj\fR or \fBTcl_RegExpCompile\fR.
+.AP "const char" *start in
+If \fItext\fR is just a portion of some other string, this argument
+identifies the beginning of the larger string.
+If it is not the same as \fItext\fR, then no
+.QW \fB^\fR
+matches will be allowed.
+.AP int index in
+Specifies which range is desired: 0 means the range of the entire
+match, 1 or greater means the range that matched a parenthesized
+sub-expression.
+.AP "const char" **startPtr out
+The address of the first character in the range is stored here, or
+NULL if there is no such range.
+.AP "const char" **endPtr out
+The address of the character just after the last one in the range
+is stored here, or NULL if there is no such range.
+.AP int cflags in
+OR-ed combination of the compilation flags \fBTCL_REG_ADVANCED\fR,
+\fBTCL_REG_EXTENDED\fR, \fBTCL_REG_BASIC\fR, \fBTCL_REG_EXPANDED\fR,
+\fBTCL_REG_QUOTE\fR, \fBTCL_REG_NOCASE\fR, \fBTCL_REG_NEWLINE\fR,
+\fBTCL_REG_NLSTOP\fR, \fBTCL_REG_NLANCH\fR, \fBTCL_REG_NOSUB\fR, and
+\fBTCL_REG_CANMATCH\fR. See below for more information.
+.AP int offset in
+The character offset into the text where matching should begin.
+The value of the offset has no impact on \fB^\fR matches. This
+behavior is controlled by \fIeflags\fR.
+.AP int nmatches in
+The number of matching subexpressions that should be remembered for
+later use. If this value is 0, then no subexpression match
+information will be computed. If the value is \-1, then
+all of the matching subexpressions will be remembered. Any other
+value will be taken as the maximum number of subexpressions to
+remember.
+.AP int eflags in
+OR-ed combination of the execution flags \fBTCL_REG_NOTBOL\fR and
+\fBTCL_REG_NOTEOL\fR. See below for more information.
+.AP Tcl_RegExpInfo *infoPtr out
+The address of the location where information about a previous match
+should be stored by \fBTcl_RegExpGetInfo\fR.
+.BE
+.SH DESCRIPTION
+.PP
+\fBTcl_RegExpMatch\fR determines whether its \fIpattern\fR argument
+matches \fIregexp\fR, where \fIregexp\fR is interpreted
+as a regular expression using the rules in the \fBre_syntax\fR
+reference page.
+If there is a match then \fBTcl_RegExpMatch\fR returns 1.
+If there is no match then \fBTcl_RegExpMatch\fR returns 0.
+If an error occurs in the matching process (e.g. \fIpattern\fR
+is not a valid regular expression) then \fBTcl_RegExpMatch\fR
+returns \-1 and leaves an error message in the interpreter result.
+\fBTcl_RegExpMatchObj\fR is similar to \fBTcl_RegExpMatch\fR except it
+operates on the Tcl values \fItextObj\fR and \fIpatObj\fR instead of
+UTF strings.
+\fBTcl_RegExpMatchObj\fR is generally more efficient than
+\fBTcl_RegExpMatch\fR, so it is the preferred interface.
+.PP
+\fBTcl_RegExpCompile\fR, \fBTcl_RegExpExec\fR, and \fBTcl_RegExpRange\fR
+provide lower-level access to the regular expression pattern matcher.
+\fBTcl_RegExpCompile\fR compiles a regular expression string into
+the internal form used for efficient pattern matching.
+The return value is a token for this compiled form, which can be
+used in subsequent calls to \fBTcl_RegExpExec\fR or \fBTcl_RegExpRange\fR.
+If an error occurs while compiling the regular expression then
+\fBTcl_RegExpCompile\fR returns NULL and leaves an error message
+in the interpreter result.
+Note: the return value from \fBTcl_RegExpCompile\fR is only valid
+up to the next call to \fBTcl_RegExpCompile\fR; it is not safe to
+retain these values for long periods of time.
+.PP
+\fBTcl_RegExpExec\fR executes the regular expression pattern matcher.
+It returns 1 if \fItext\fR contains a range of characters that
+match \fIregexp\fR, 0 if no match is found, and
+\-1 if an error occurs.
+In the case of an error, \fBTcl_RegExpExec\fR leaves an error
+message in the interpreter result.
+When searching a string for multiple matches of a pattern,
+it is important to distinguish between the start of the original
+string and the start of the current search.
+For example, when searching for the second occurrence of a
+match, the \fItext\fR argument might point to the character
+just after the first match; however, it is important for the
+pattern matcher to know that this is not the start of the entire string,
+so that it does not allow
+.QW \fB^\fR
+atoms in the pattern to match.
+The \fIstart\fR argument provides this information by pointing
+to the start of the overall string containing \fItext\fR.
+\fIStart\fR will be less than or equal to \fItext\fR; if it
+is less than \fItext\fR then no \fB^\fR matches will be allowed.
+.PP
+\fBTcl_RegExpRange\fR may be invoked after \fBTcl_RegExpExec\fR
+returns; it provides detailed information about what ranges of
+the string matched what parts of the pattern.
+\fBTcl_RegExpRange\fR returns a pair of pointers in \fI*startPtr\fR
+and \fI*endPtr\fR that identify a range of characters in
+the source string for the most recent call to \fBTcl_RegExpExec\fR.
+\fIIndex\fR indicates which of several ranges is desired:
+if \fIindex\fR is 0, information is returned about the overall range
+of characters that matched the entire pattern; otherwise,
+information is returned about the range of characters that matched the
+\fIindex\fR'th parenthesized subexpression within the pattern.
+If there is no range corresponding to \fIindex\fR then NULL
+is stored in \fI*startPtr\fR and \fI*endPtr\fR.
+.PP
+\fBTcl_GetRegExpFromObj\fR, \fBTcl_RegExpExecObj\fR, and
+\fBTcl_RegExpGetInfo\fR are value interfaces that provide the most
+direct control of Henry Spencer's regular expression library. For
+users that need to modify compilation and execution options directly,
+it is recommended that you use these interfaces instead of calling the
+internal regexp functions. These interfaces handle the details of UTF
+to Unicode translations as well as providing improved performance
+through caching in the pattern and string values.
+.PP
+\fBTcl_GetRegExpFromObj\fR attempts to return a compiled regular
+expression from the \fIpatObj\fR. If the value does not already
+contain a compiled regular expression it will attempt to create one
+from the string in the value and assign it to the internal
+representation of the \fIpatObj\fR. The return value of this function
+is of type \fBTcl_RegExp\fR. The return value is a token for this
+compiled form, which can be used in subsequent calls to
+\fBTcl_RegExpExecObj\fR or \fBTcl_RegExpGetInfo\fR. If an error
+occurs while compiling the regular expression then
+\fBTcl_GetRegExpFromObj\fR returns NULL and leaves an error message in
+the interpreter result. The regular expression token can be used as
+long as the internal representation of \fIpatObj\fR refers to the
+compiled form. The \fIcflags\fR argument is a bit-wise OR of
+zero or more of the following flags that control the compilation of
+\fIpatObj\fR:
+.RS 2
+.TP
+\fBTCL_REG_ADVANCED\fR
+Compile advanced regular expressions
+.PQ ARE s .
+This mode corresponds to
+the normal regular expression syntax accepted by the Tcl \fBregexp\fR and
+\fBregsub\fR commands.
+.TP
+\fBTCL_REG_EXTENDED\fR
+Compile extended regular expressions
+.PQ ERE s .
+This mode corresponds
+to the regular expression syntax recognized by Tcl 8.0 and earlier
+versions.
+.TP
+\fBTCL_REG_BASIC\fR
+Compile basic regular expressions
+.PQ BRE s .
+This mode corresponds
+to the regular expression syntax recognized by common Unix utilities
+like \fBsed\fR and \fBgrep\fR. This is the default if no flags are
+specified.
+.TP
+\fBTCL_REG_EXPANDED\fR
+Compile the regular expression (basic, extended, or advanced) using an
+expanded syntax that allows comments and whitespace. This mode causes
+non-backslashed non-bracket-expression white
+space and #-to-end-of-line comments to be ignored.
+.TP
+\fBTCL_REG_QUOTE\fR
+Compile a literal string, with all characters treated as ordinary characters.
+.TP
+\fBTCL_REG_NOCASE\fR
+Compile for matching that ignores upper/lower case distinctions.
+.TP
+\fBTCL_REG_NEWLINE\fR
+Compile for newline-sensitive matching. By default, newline is a
+completely ordinary character with no special meaning in either
+regular expressions or strings. With this flag,
+.QW [^
+bracket expressions and
+.QW .
+never match newline,
+.QW ^
+matches an empty string
+after any newline in addition to its normal function, and
+.QW $
+matches
+an empty string before any newline in addition to its normal function.
+\fBREG_NEWLINE\fR is the bit-wise OR of \fBREG_NLSTOP\fR and
+\fBREG_NLANCH\fR.
+.TP
+\fBTCL_REG_NLSTOP\fR
+Compile for partial newline-sensitive matching,
+with the behavior of
+.QW [^
+bracket expressions and
+.QW .
+affected, but not the behavior of
+.QW ^
+and
+.QW $ .
+In this mode,
+.QW [^
+bracket expressions and
+.QW .
+never match newline.
+.TP
+\fBTCL_REG_NLANCH\fR
+Compile for inverse partial newline-sensitive matching,
+with the behavior of
+.QW ^
+and
+.QW $
+(the
+.QW anchors )
+affected, but not the behavior of
+.QW [^
+bracket expressions and
+.QW . .
+In this mode
+.QW ^
+matches an empty string
+after any newline in addition to its normal function, and
+.QW $
+matches
+an empty string before any newline in addition to its normal function.
+.TP
+\fBTCL_REG_NOSUB\fR
+Compile for matching that reports only success or failure,
+not what was matched. This reduces compile overhead and may improve
+performance. Subsequent calls to \fBTcl_RegExpGetInfo\fR or
+\fBTcl_RegExpRange\fR will not report any match information.
+.TP
+\fBTCL_REG_CANMATCH\fR
+Compile for matching that reports the potential to complete a partial
+match given more text (see below).
+.RE
+.PP
+Only one of
+\fBTCL_REG_EXTENDED\fR,
+\fBTCL_REG_ADVANCED\fR,
+\fBTCL_REG_BASIC\fR, and
+\fBTCL_REG_QUOTE\fR may be specified.
+.PP
+\fBTcl_RegExpExecObj\fR executes the regular expression pattern
+matcher. It returns 1 if \fIobjPtr\fR contains a range of characters
+that match \fIregexp\fR, 0 if no match is found, and \-1 if an error
+occurs. In the case of an error, \fBTcl_RegExpExecObj\fR leaves an
+error message in the interpreter result. The \fInmatches\fR value
+indicates to the matcher how many subexpressions are of interest. If
+\fInmatches\fR is 0, then no subexpression match information is
+recorded, which may allow the matcher to make various optimizations.
+If the value is \-1, then all of the subexpressions in the pattern are
+remembered. If the value is a positive integer, then only that number
+of subexpressions will be remembered. Matching begins at the
+specified Unicode character index given by \fIoffset\fR. Unlike
+\fBTcl_RegExpExec\fR, the behavior of anchors is not affected by the
+offset value. Instead the behavior of the anchors is explicitly
+controlled by the \fIeflags\fR argument, which is a bit-wise OR of
+zero or more of the following flags:
+.RS 2
+.TP
+\fBTCL_REG_NOTBOL\fR
+The starting character will not be treated as the beginning of a
+line or the beginning of the string, so
+.QW ^
+will not match there.
+Note that this flag has no effect on how
+.QW \fB\eA\fR
+matches.
+.TP
+\fBTCL_REG_NOTEOL\fR
+The last character in the string will not be treated as the end of a
+line or the end of the string, so
+.QW $
+will not match there.
+Note that this flag has no effect on how
+.QW \fB\eZ\fR
+matches.
+.RE
+.PP
+\fBTcl_RegExpGetInfo\fR retrieves information about the last match
+performed with a given regular expression \fIregexp\fR. The
+\fIinfoPtr\fR argument contains a pointer to a structure that is
+defined as follows:
+.PP
+.CS
+typedef struct Tcl_RegExpInfo {
+ int \fInsubs\fR;
+ Tcl_RegExpIndices *\fImatches\fR;
+ long \fIextendStart\fR;
+} \fBTcl_RegExpInfo\fR;
+.CE
+.PP
+The \fInsubs\fR field contains a count of the number of parenthesized
+subexpressions within the regular expression. If the \fBTCL_REG_NOSUB\fR
+was used, then this value will be zero. The \fImatches\fR field
+points to an array of \fInsubs\fR+1 values that indicate the bounds of each
+subexpression matched. The first element in the array refers to the
+range matched by the entire regular expression, and subsequent elements
+refer to the parenthesized subexpressions in the order that they
+appear in the pattern. Each element is a structure that is defined as
+follows:
+.PP
+.CS
+typedef struct Tcl_RegExpIndices {
+ long \fIstart\fR;
+ long \fIend\fR;
+} \fBTcl_RegExpIndices\fR;
+.CE
+.PP
+The \fIstart\fR and \fIend\fR values are Unicode character indices
+relative to the offset location within \fIobjPtr\fR where matching began.
+The \fIstart\fR index identifies the first character of the matched
+subexpression. The \fIend\fR index identifies the first character
+after the matched subexpression. If the subexpression matched the
+empty string, then \fIstart\fR and \fIend\fR will be equal. If the
+subexpression did not participate in the match, then \fIstart\fR and
+\fIend\fR will be set to \-1.
+.PP
+The \fIextendStart\fR field in \fBTcl_RegExpInfo\fR is only set if the
+\fBTCL_REG_CANMATCH\fR flag was used. It indicates the first
+character in the string where a match could occur. If a match was
+found, this will be the same as the beginning of the current match.
+If no match was found, then it indicates the earliest point at which a
+match might occur if additional text is appended to the string. If it
+is no match is possible even with further text, this field will be set
+to \-1.
+.SH "SEE ALSO"
+re_syntax(n)
+.SH KEYWORDS
+match, pattern, regular expression, string, subexpression, Tcl_RegExpIndices, Tcl_RegExpInfo
OSDN Git Service
