.TH Regexp 3I "23 May 1989" "InterViews" "InterViews Reference Manual"
.SH NAME
Regexp \- regular expression searching
.SH SYNOPSIS
.B #include <InterViews/regexp.h>
.SH DESCRIPTION
A Regexp encapsulates a regular expression pattern and defines
operations for searching and matching the pattern against a string.
The syntax of the regular expression pattern is the same as that for
ed(1).  Information can be obtained about the most recent match of the
regular expression (and its sub-expressions).
.SH PUBLIC OPERATIONS
.TP
.B "Regexp(const char* pattern)"
.ns
.TP
.B "Regexp(const char* pattern, int length)"
Construct a new Regexp for \fIpattern\fP.
.TP
.B "int Match(const char* text, int length, int index)"
Attempt a match against \fItext\fP (of length \fIlength\fP) at
position \fIindex\fP.  The return value is the length of the matching
string, or a negative number if the match failed.
.TP
.B "int Search(const char* text, int length, int index, int range)"
Search for a match in the string \fItext\fP (of length \fIlength\fP).
Matches are attempted starting at positions between \fIindex\fP and
\fIindex\fP plus \fIrange\fP.  If \fIrange\fP is positive the first
match after \fIindex\fP is reported.  If \fIrange\fP is negative the
first match before \fIindex\fP is reported.  The return value is the
index of the starting position of the match, or a negative number if
there is no match in the specified range.
.TP
.B "int BeginningOfMatch(int subexp)"
.ns
.TP
.B "int EndOfMatch(int subexp)"
Return information about the most recent match.  If
\fIsubexp\fP is zero (the default), information is reported for the
complete regular expression.  Other values of \fIsubexp\fP refer to
sub-expressions in the pattern.  For example, if \fIsubexp\fP is 2,
information is returned for the sub-expression specified by the second
pair of \\( and \\) delimiters in the pattern.
.SH SEE ALSO
ed(1)