diff options
Diffstat (limited to 'doc/regsub.n')
-rw-r--r-- | doc/regsub.n | 62 |
1 files changed, 44 insertions, 18 deletions
diff --git a/doc/regsub.n b/doc/regsub.n index fecc357..84514fc 100644 --- a/doc/regsub.n +++ b/doc/regsub.n @@ -6,7 +6,7 @@ '\" See the file "license.terms" for information on usage and redistribution '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. '\" -'\" RCS: @(#) $Id: regsub.n,v 1.20 2007/10/28 14:17:40 dkf Exp $ +'\" RCS: @(#) $Id: regsub.n,v 1.21 2007/10/29 01:42:19 dkf Exp $ '\" .so man.macros .TH regsub n 8.3 Tcl "Tcl Built-In Commands" @@ -17,7 +17,6 @@ regsub \- Perform substitutions based on regular expression pattern matching .SH SYNOPSIS \fBregsub \fR?\fIswitches\fR? \fIexp string subSpec \fR?\fIvarName\fR? .BE - .SH DESCRIPTION .PP This command matches the regular expression \fIexp\fR against @@ -31,18 +30,26 @@ If there is a match, then while copying \fIstring\fR to \fIvarName\fR (or to the result of this command if \fIvarName\fR is not present) the portion of \fIstring\fR that matched \fIexp\fR is replaced with \fIsubSpec\fR. -If \fIsubSpec\fR contains a ``&'' or ``\e0'', then it is replaced -in the substitution with the portion of \fIstring\fR that -matched \fIexp\fR. -If \fIsubSpec\fR contains a ``\e\fIn\fR'', where \fIn\fR is a digit +If \fIsubSpec\fR contains a +.QW & +or +.QW \e0 , +then it is replaced in the substitution with the portion of +\fIstring\fR that matched \fIexp\fR. +If \fIsubSpec\fR contains a +.QW \e\fIn\fR , +where \fIn\fR is a digit between 1 and 9, then it is replaced in the substitution with -the portion of \fIstring\fR that matched the \fIn\fR-th +the portion of \fIstring\fR that matched the \fIn\fR'th parenthesized subexpression of \fIexp\fR. Additional backslashes may be used in \fIsubSpec\fR to prevent special -interpretation of ``&'' or ``\e0'' or ``\e\fIn\fR'' or -backslash. +interpretation of +.QW & , +.QW \e0 , +.QW \e\fIn\fR +and backslashes. The use of backslashes in \fIsubSpec\fR tends to interact badly -with the Tcl parser's use of backslashes, so it's generally +with the Tcl parser's use of backslashes, so it is generally safest to enclose \fIsubSpec\fR in braces if it includes backslashes. .LP @@ -55,7 +62,10 @@ All ranges in \fIstring\fR that match \fIexp\fR are found and substitution is performed for each of these ranges. Without this switch only the first matching range is found and substituted. -If \fB\-all\fR is specified, then ``&'' and ``\e\fIn\fR'' +If \fB\-all\fR is specified, then +.QW & +and +.QW \e\fIn\fR sequences are handled for each substitution using the information from the corresponding match. .TP 15 @@ -66,21 +76,37 @@ the \fB(?x)\fR embedded option (see the \fBre_syntax\fR manual page). .TP 15 \fB\-line\fR Enables newline-sensitive matching. By default, newline is a -completely ordinary character with no special meaning. With this -flag, `[^' bracket expressions and `.' never match newline, `^' +completely ordinary character with no special meaning. 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 `$' matches an empty string before any newline in +function, and +.QW $ +matches an empty string before any newline in addition to its normal function. This flag is equivalent to specifying both \fB\-linestop\fR and \fB\-lineanchor\fR, or the \fB(?n)\fR embedded option (see the \fBre_syntax\fR manual page). .TP 15 \fB\-linestop\fR -Changes the behavior of `[^' bracket expressions and `.' so that they +Changes the behavior of +.QW [^ +bracket expressions and +.QW . +so that they stop at newlines. This is the same as specifying the \fB(?p)\fR embedded option (see the \fBre_syntax\fR manual page). .TP 15 \fB\-lineanchor\fR -Changes the behavior of `^' and `$' (the ``anchors'') so they match the +Changes the behavior of +.QW ^ +and +.QW $ +(the +.QW anchors ) +so they match the beginning and end of a line respectively. This is the same as specifying the \fB(?w)\fR embedded option (see the \fBre_syntax\fR manual page). @@ -97,7 +123,8 @@ matching the regular expression at. The \fIindex\fR value is interpreted in the same manner as the \fIindex\fR argument to \fBstring index\fR. .VE 8.5 -When using this switch, `^' +When using this switch, +.QW ^ will not match the beginning of the line, and \eA will still match the start of the string at \fIindex\fR. \fIindex\fR will be constrained to the bounds of the input string. @@ -137,7 +164,6 @@ set substitution {[format \e\e\e\eu%04x [scan "\e\e&" %c]]} # will perform the computational parts of the conversion. set quoted [subst [\fBregsub\fR -all $RE $string $substitution]] .CE - .SH "SEE ALSO" regexp(n), re_syntax(n), subst(n), .VS 8.5 |