Include RE2 library

third_party/re2/re2/unicode_groups.h

Index: third_party/re2/re2/unicode_groups.h
diff --git a/third_party/re2/re2/unicode_groups.h b/third_party/re2/re2/unicode_groups.h
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+// Copyright 2008 The RE2 Authors.  All Rights Reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Unicode character groups.
+
+// The codes get split into ranges of 16-bit codes
+// and ranges of 32-bit codes.  It would be simpler
+// to use only 32-bit ranges, but these tables are large
+// enough to warrant extra care.
+//
+// Using just 32-bit ranges gives 27 kB of data.
+// Adding 16-bit ranges gives 18 kB of data.
+// Adding an extra table of 16-bit singletons would reduce
+// to 16.5 kB of data but make the data harder to use;
+// we don't bother.
+
+#ifndef RE2_UNICODE_GROUPS_H__
+#define RE2_UNICODE_GROUPS_H__
+
+#include "util/util.h"
+
+namespace re2 {
+
+struct URange16
+{
+  uint16 lo;
+  uint16 hi;
+};
+
+struct URange32
+{
+  uint32 lo;
+  uint32 hi;
+};
+
+struct UGroup
+{
+  const char *name;
+  int sign;  // +1 for [abc], -1 for [^abc]
+  URange16 *r16;
+  int nr16;
+  URange32 *r32;
+  int nr32;
+};
+
+// Named by property or script name (e.g., "Nd", "N", "Han").
+// Negated groups are not included.
+extern UGroup unicode_groups[];
+extern int num_unicode_groups;
+
+// Named by POSIX name (e.g., "[:alpha:]", "[:^lower:]").
+// Negated groups are included.
+extern UGroup posix_groups[];
+extern int num_posix_groups;
+
+// Named by Perl name (e.g., "\\d", "\\D").
+// Negated groups are included.
+extern UGroup perl_groups[];
+extern int num_perl_groups;
+
+}  // namespace re2
+
+#endif  // RE2_UNICODE_GROUPS_H__