Move files around to prepare for assimilation into core

[libs/core.git] / source / strings / regmatch.h

diff --git a/source/strings/regmatch.h b/source/strings/regmatch.h
new file mode 100644 (file)
index 0000000..19cac11
--- /dev/null
+++ b/source/strings/regmatch.h
@@ -0,0 +1,81 @@
+/* $Id$
+
+This file is part of libmspstrings
+Copyright © 2007 Mikko Rasa
+Distributed under the LGPL
+*/
+
+#ifndef MSP_STRINGS_REGMATCH_H_
+#define MSP_STRINGS_REGMATCH_H_
+
+#include <string>
+#include <vector>
+
+namespace Msp {
+
+/**
+This class stores the result of a Regex being matched against a string.  If the
+match was successful, the RegMatch object evaluates to true.
+
+A RegMatch representing a successful match has one or more groups, indicating
+matching parts of the string.  The first group (with index 0) indicates the
+part matched by the whole regex.  Further groups, if present, indicate parts
+matched by subregexes.  These are ordered from left to right, by the opening
+parenthesis of the subregex.
+*/
+class RegMatch
+{
+public:
+       /**
+       A single subregex of the match.
+       */
+       struct Group
+       {
+               bool match;       //< Whether or not this group matched
+               unsigned begin;   //< First offset of the match
+               unsigned end;     //< One-past-last offset
+               unsigned length;  //< Length of the match (end-begin)
+               std::string str;  //< The part of the string that matched
+
+               Group(): match(false) { }
+               operator bool() const { return match; }
+       };
+
+       typedef std::vector<Group> GroupArray;
+
+private:
+       GroupArray groups;
+
+public:
+       /** Constructs a RegMatch representing a non-match. */
+       RegMatch() { }
+
+       /** Constructs a new RegMatch from a string and groups.  The length and str
+       members of each group are computed and need not be set.  Intended to be used
+       by the Regex class. */
+       RegMatch(const std::string &, const std::vector<Group> &);
+
+       /** Returns a reference to a single group in the match. */
+       const Group &group(unsigned) const;
+
+       /** Returns true if the RegMatch object represents a non-match. */
+       bool empty() const { return groups.empty(); }
+
+       /** Returns the number of groups in this match. */
+       unsigned size() const { return groups.size(); }
+
+       /** Returns the begin offset of the whole match. */
+       unsigned begin() const { return groups.empty() ? 0 : groups[0].begin; }
+
+       /** Returns the end offset of the whole match. */
+       unsigned end() const { return groups.empty() ? 0 : groups[0].end; }
+
+       /** Shorthand for the group() function. */
+       const Group &operator[](unsigned i) const { return group(i); }
+
+       operator bool() const { return !empty(); }
+};
+
+} // namespace Msp
+
+#endif