Include RE2 library

third_party/re2/re2/re2.h

+// Copyright 2003-2009 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.
+
+#ifndef RE2_RE2_H
+#define RE2_RE2_H
+
+#define kDefaultMaxMem (8<<20)
+
+// C++ interface to the re2 regular-expression library.
+// RE2 supports Perl-style regular expressions (with extensions like
+// \d, \w, \s, ...).
+//
+// -----------------------------------------------------------------------
+// REGEXP SYNTAX:
+//
+// This module uses the re2 library and hence supports
+// its syntax for regular expressions, which is similar to Perl's with
+// some of the more complicated things thrown away.  In particular,
+// backreferences and generalized assertions are not available, nor is \Z.
+//
+// See http://code.google.com/p/re2/wiki/Syntax for the syntax
+// supported by RE2, and a comparison with PCRE and PERL regexps.
+//
+// For those not familiar with Perl's regular expressions,
+// here are some examples of the most commonly used extensions:
+//
+//   "hello (\\w+) world"  -- \w matches a "word" character
+//   "version (\\d+)"      -- \d matches a digit
+//   "hello\\s+world"      -- \s matches any whitespace character
+//   "\\b(\\w+)\\b"        -- \b matches non-empty string at word boundary
+//   "(?i)hello"           -- (?i) turns on case-insensitive matching
+//   "/\\*(.*?)\\*/"       -- .*? matches . minimum no. of times possible
+//
+// -----------------------------------------------------------------------
+// MATCHING INTERFACE:
+//
+// The "FullMatch" operation checks that supplied text matches a
+// supplied pattern exactly.
+//
+// Example: successful match
+//    CHECK(RE2::FullMatch("hello", "h.*o"));
+//
+// Example: unsuccessful match (requires full match):
+//    CHECK(!RE2::FullMatch("hello", "e"));
+//
+// -----------------------------------------------------------------------
+// UTF-8 AND THE MATCHING INTERFACE:
+//
+// By default, the pattern and input text are interpreted as UTF-8.
+// The RE2::Latin1 option causes them to be interpreted as Latin-1.
+//
+// Example:
+//    CHECK(RE2::FullMatch(utf8_string, RE2(utf8_pattern)));
+//    CHECK(RE2::FullMatch(latin1_string, RE2(latin1_pattern, RE2::Latin1)));
+//
+// -----------------------------------------------------------------------
+// MATCHING WITH SUB-STRING EXTRACTION:
+//
+// You can supply extra pointer arguments to extract matched subpieces.
+//
+// Example: extracts "ruby" into "s" and 1234 into "i"
+//    int i;
+//    string s;
+//    CHECK(RE2::FullMatch("ruby:1234", "(\\w+):(\\d+)", &s, &i));
+//
+// Example: fails because string cannot be stored in integer
+//    CHECK(!RE2::FullMatch("ruby", "(.*)", &i));
+//
+// Example: fails because there aren't enough sub-patterns:
+//    CHECK(!RE2::FullMatch("ruby:1234", "\\w+:\\d+", &s));
+//
+// Example: does not try to extract any extra sub-patterns
+//    CHECK(RE2::FullMatch("ruby:1234", "(\\w+):(\\d+)", &s));
+//
+// Example: does not try to extract into NULL
+//    CHECK(RE2::FullMatch("ruby:1234", "(\\w+):(\\d+)", NULL, &i));
+//
+// Example: integer overflow causes failure
+//    CHECK(!RE2::FullMatch("ruby:1234567891234", "\\w+:(\\d+)", &i));
+//
+// NOTE(rsc): Asking for substrings slows successful matches quite a bit.
+// This may get a little faster in the future, but right now is slower
+// than PCRE.  On the other hand, failed matches run *very* fast (faster
+// than PCRE), as do matches without substring extraction.
+//
+// -----------------------------------------------------------------------
+// PARTIAL MATCHES
+//
+// You can use the "PartialMatch" operation when you want the pattern
+// to match any substring of the text.
+//
+// Example: simple search for a string:
+//      CHECK(RE2::PartialMatch("hello", "ell"));
+//
+// Example: find first number in a string
+//      int number;
+//      CHECK(RE2::PartialMatch("x*100 + 20", "(\\d+)", &number));
+//      CHECK_EQ(number, 100);
+//
+// -----------------------------------------------------------------------
+// PRE-COMPILED REGULAR EXPRESSIONS
+//
+// RE2 makes it easy to use any string as a regular expression, without
+// requiring a separate compilation step.
+//
+// If speed is of the essence, you can create a pre-compiled "RE2"
+// object from the pattern and use it multiple times.  If you do so,
+// you can typically parse text faster than with sscanf.
+//
+// Example: precompile pattern for faster matching:
+//    RE2 pattern("h.*o");
+//    while (ReadLine(&str)) {
+//      if (RE2::FullMatch(str, pattern)) ...;
+//    }
+//
+// -----------------------------------------------------------------------
+// SCANNING TEXT INCREMENTALLY
+//
+// The "Consume" operation may be useful if you want to repeatedly
+// match regular expressions at the front of a string and skip over
+// them as they match.  This requires use of the "StringPiece" type,
+// which represents a sub-range of a real string.
+//
+// Example: read lines of the form "var = value" from a string.
+//      string contents = ...;          // Fill string somehow
+//      StringPiece input(contents);    // Wrap a StringPiece around it
+//
+//      string var;
+//      int value;
+//      while (RE2::Consume(&input, "(\\w+) = (\\d+)\n", &var, &value)) {
+//        ...;
+//      }
+//
+// Each successful call to "Consume" will set "var/value", and also
+// advance "input" so it points past the matched text.  Note that if the
+// regular expression matches an empty string, input will advance
+// by 0 bytes.  If the regular expression being used might match
+// an empty string, the loop body must check for this case and either
+// advance the string or break out of the loop.
+//
+// The "FindAndConsume" operation is similar to "Consume" but does not
+// anchor your match at the beginning of the string.  For example, you
+// could extract all words from a string by repeatedly calling
+//     RE2::FindAndConsume(&input, "(\\w+)", &word)
+//
+// -----------------------------------------------------------------------
+// USING VARIABLE NUMBER OF ARGUMENTS
+//
+// The above operations require you to know the number of arguments
+// when you write the code.  This is not always possible or easy (for
+// example, the regular expression may be calculated at run time).
+// You can use the "N" version of the operations when the number of
+// match arguments are determined at run time.
+//
+// Example:
+//   const RE2::Arg* args[10];
+//   int n;
+//   // ... populate args with pointers to RE2::Arg values ...
+//   // ... set n to the number of RE2::Arg objects ...
+//   bool match = RE2::FullMatchN(input, pattern, args, n);
+//
+// The last statement is equivalent to
+//
+//   bool match = RE2::FullMatch(input, pattern,
+//                               *args[0], *args[1], ..., *args[n - 1]);
+//
+// -----------------------------------------------------------------------
+// PARSING HEX/OCTAL/C-RADIX NUMBERS
+//
+// By default, if you pass a pointer to a numeric value, the
+// corresponding text is interpreted as a base-10 number.  You can
+// instead wrap the pointer with a call to one of the operators Hex(),
+// Octal(), or CRadix() to interpret the text in another base.  The
+// CRadix operator interprets C-style "0" (base-8) and "0x" (base-16)
+// prefixes, but defaults to base-10.
+//
+// Example:
+//   int a, b, c, d;
+//   CHECK(RE2::FullMatch("100 40 0100 0x40", "(.*) (.*) (.*) (.*)",
+//         RE2::Octal(&a), RE2::Hex(&b), RE2::CRadix(&c), RE2::CRadix(&d));
+// will leave 64 in a, b, c, and d.
+
+
+#include <stdint.h>
+#include <map>
+#include <string>
+#include "re2/stringpiece.h"
+#include "re2/variadic_function.h"
+
+namespace re2 {
+using std::string;
+using std::map;
+class Mutex;
+class Prog;
+class Regexp;
+
+// Interface for regular expression matching.  Also corresponds to a
+// pre-compiled regular expression.  An "RE2" object is safe for
+// concurrent use by multiple threads.
+class RE2 {
+ public:
+  // We convert user-passed pointers into special Arg objects
+  class Arg;
+  class Options;
+
+  // Defined in set.h.
+  class Set;
+
+  enum ErrorCode {
+    NoError = 0,
+
+    // Unexpected error
+    ErrorInternal,
+
+    // Parse errors
+    ErrorBadEscape,          // bad escape sequence
+    ErrorBadCharClass,       // bad character class
+    ErrorBadCharRange,       // bad character class range
+    ErrorMissingBracket,     // missing closing ]
+    ErrorMissingParen,       // missing closing )
+    ErrorTrailingBackslash,  // trailing \ at end of regexp
+    ErrorRepeatArgument,     // repeat argument missing, e.g. "*"
+    ErrorRepeatSize,         // bad repetition argument
+    ErrorRepeatOp,           // bad repetition operator
+    ErrorBadPerlOp,          // bad perl operator
+    ErrorBadUTF8,            // invalid UTF-8 in regexp
+    ErrorBadNamedCapture,    // bad named capture group
+    ErrorPatternTooLarge,    // pattern too large (compile failed)
+  };
+
+  // Predefined common options.
+  // If you need more complicated things, instantiate
+  // an Option class, change the settings, and pass it to the
+  // RE2 constructor.
+  static const Options DefaultOptions;
+  static const Options Latin1; // treat input as Latin-1 (default UTF-8)
+  //static const Options POSIX;  // POSIX syntax, leftmost-longest match
+  static const Options Quiet;  // do not log about regexp parse errors
+
+  // Need to have the const char* and const string& forms for implicit
+  // conversions when passing string literals to FullMatch and PartialMatch.
+  // Otherwise the StringPiece form would be sufficient.
+#ifndef SWIG
+  RE2(const char* pattern);
+  RE2(const string& pattern);
+#endif
+  RE2(const StringPiece& pattern);
+  RE2(const StringPiece& pattern, const Options& option);
+  ~RE2();
+
+  // Returns whether RE2 was created properly.
+  bool ok() const { return error_code() == NoError; }
+
+  // The string specification for this RE2.  E.g.
+  //   RE2 re("ab*c?d+");
+  //   re.pattern();    // "ab*c?d+"
+  const string& pattern() const { return pattern_; }
+
+  // If RE2 could not be created properly, returns an error string.
+  // Else returns the empty string.
+  const string& error() const { return *error_; }
+
+  // If RE2 could not be created properly, returns an error code.
+  // Else returns RE2::NoError (== 0).
+  ErrorCode error_code() const { return error_code_; }
+
+  // If RE2 could not be created properly, returns the offending
+  // portion of the regexp.
+  const string& error_arg() const { return error_arg_; }
+
+  // Returns the program size, a very approximate measure of a regexp's "cost".
+  // Larger numbers are more expensive than smaller numbers.
+  int ProgramSize() const;
+
+  // Returns the underlying Regexp; not for general use.
+  // Returns entire_regexp_ so that callers don't need
+  // to know about prefix_ and prefix_foldcase_.
+  re2::Regexp* Regexp() const { return entire_regexp_; }
+
+  /***** The useful part: the matching interface *****/
+
+  // Matches "text" against "pattern".  If pointer arguments are
+  // supplied, copies matched sub-patterns into them.
+  //
+  // You can pass in a "const char*" or a "string" for "text".
+  // You can pass in a "const char*" or a "string" or a "RE2" for "pattern".
+  //
+  // The provided pointer arguments can be pointers to any scalar numeric
+  // type, or one of:
+  //    string          (matched piece is copied to string)
+  //    StringPiece     (StringPiece is mutated to point to matched piece)
+  //    T               (where "bool T::ParseFrom(const char*, int)" exists)
+  //    (void*)NULL     (the corresponding matched sub-pattern is not copied)
+  //
+  // Returns true iff all of the following conditions are satisfied:
+  //   a. "text" matches "pattern" exactly
+  //   b. The number of matched sub-patterns is >= number of supplied pointers
+  //   c. The "i"th argument has a suitable type for holding the
+  //      string captured as the "i"th sub-pattern.  If you pass in
+  //      NULL for the "i"th argument, or pass fewer arguments than
+  //      number of sub-patterns, "i"th captured sub-pattern is
+  //      ignored.
+  //
+  // CAVEAT: An optional sub-pattern that does not exist in the
+  // matched string is assigned the empty string.  Therefore, the
+  // following will return false (because the empty string is not a
+  // valid number):
+  //    int number;
+  //    RE2::FullMatch("abc", "[a-z]+(\\d+)?", &number);
+  static bool FullMatchN(const StringPiece& text, const RE2& re,
+                         const Arg* const args[], int argc);
+  static const VariadicFunction2<
+      bool, const StringPiece&, const RE2&, Arg, RE2::FullMatchN> FullMatch;
+
+  // Exactly like FullMatch(), except that "pattern" is allowed to match
+  // a substring of "text".
+  static bool PartialMatchN(const StringPiece& text, const RE2& re, // 3..16 args
+                            const Arg* const args[], int argc);
+  static const VariadicFunction2<
+      bool, const StringPiece&, const RE2&, Arg, RE2::PartialMatchN> PartialMatch;
+
+  // Like FullMatch() and PartialMatch(), except that pattern has to
+  // match a prefix of "text", and "input" is advanced past the matched
+  // text.  Note: "input" is modified iff this routine returns true.
+  static bool ConsumeN(StringPiece* input, const RE2& pattern, // 3..16 args
+                       const Arg* const args[], int argc);
+  static const VariadicFunction2<
+      bool, StringPiece*, const RE2&, Arg, RE2::ConsumeN> Consume;
+
+  // Like Consume(..), but does not anchor the match at the beginning of the
+  // string.  That is, "pattern" need not start its match at the beginning of
+  // "input".  For example, "FindAndConsume(s, "(\\w+)", &word)" finds the next
+  // word in "s" and stores it in "word".
+  static bool FindAndConsumeN(StringPiece* input, const RE2& pattern,
+                             const Arg* const args[], int argc);
+  static const VariadicFunction2<
+      bool, StringPiece*, const RE2&, Arg, RE2::FindAndConsumeN> FindAndConsume;
+
+  // Replace the first match of "pattern" in "str" with "rewrite".
+  // Within "rewrite", backslash-escaped digits (\1 to \9) can be
+  // used to insert text matching corresponding parenthesized group
+  // from the pattern.  \0 in "rewrite" refers to the entire matching
+  // text.  E.g.,
+  //
+  //   string s = "yabba dabba doo";
+  //   CHECK(RE2::Replace(&s, "b+", "d"));
+  //
+  // will leave "s" containing "yada dabba doo"
+  //
+  // Returns true if the pattern matches and a replacement occurs,
+  // false otherwise.
+  static bool Replace(string *str,
+                      const RE2& pattern,
+                      const StringPiece& rewrite);
+
+  // Like Replace(), except replaces successive non-overlapping occurrences
+  // of the pattern in the string with the rewrite. E.g.
+  //
+  //   string s = "yabba dabba doo";
+  //   CHECK(RE2::GlobalReplace(&s, "b+", "d"));
+  //
+  // will leave "s" containing "yada dada doo"
+  // Replacements are not subject to re-matching.
+  //
+  // Because GlobalReplace only replaces non-overlapping matches,
+  // replacing "ana" within "banana" makes only one replacement, not two.
+  //
+  // Returns the number of replacements made.
+  static int GlobalReplace(string *str,
+                           const RE2& pattern,
+                           const StringPiece& rewrite);
+
+  // Like Replace, except that if the pattern matches, "rewrite"
+  // is copied into "out" with substitutions.  The non-matching
+  // portions of "text" are ignored.
+  //
+  // Returns true iff a match occurred and the extraction happened
+  // successfully;  if no match occurs, the string is left unaffected.
+  static bool Extract(const StringPiece &text,
+                      const RE2& pattern,
+                      const StringPiece &rewrite,
+                      string *out);
+
+  // Escapes all potentially meaningful regexp characters in
+  // 'unquoted'.  The returned string, used as a regular expression,
+  // will exactly match the original string.  For example,
+  //           1.5-2.0?
+  // may become:
+  //           1\.5\-2\.0\?
+  static string QuoteMeta(const StringPiece& unquoted);
+
+  // Computes range for any strings matching regexp. The min and max can in
+  // some cases be arbitrarily precise, so the caller gets to specify the
+  // maximum desired length of string returned.
+  //
+  // Assuming PossibleMatchRange(&min, &max, N) returns successfully, any
+  // string s that is an anchored match for this regexp satisfies
+  //   min <= s && s <= max.
+  //
+  // Note that PossibleMatchRange() will only consider the first copy of an
+  // infinitely repeated element (i.e., any regexp element followed by a '*' or
+  // '+' operator). Regexps with "{N}" constructions are not affected, as those
+  // do not compile down to infinite repetitions.
+  //
+  // Returns true on success, false on error.
+  bool PossibleMatchRange(string* min, string* max, int maxlen) const;
+
+  // Generic matching interface
+
+  // Type of match.
+  enum Anchor {
+    UNANCHORED,         // No anchoring
+    ANCHOR_START,       // Anchor at start only
+    ANCHOR_BOTH,        // Anchor at start and end
+  };
+
+  // Return the number of capturing subpatterns, or -1 if the
+  // regexp wasn't valid on construction.  The overall match ($0)
+  // does not count: if the regexp is "(a)(b)", returns 2.
+  int NumberOfCapturingGroups() const;
+
+
+  // Return a map from names to capturing indices.
+  // The map records the index of the leftmost group
+  // with the given name.
+  // Only valid until the re is deleted.
+  const map<string, int>& NamedCapturingGroups() const;
+
+  // Return a map from capturing indices to names.
+  // The map has no entries for unnamed groups.
+  // Only valid until the re is deleted.
+  const map<int, string>& CapturingGroupNames() const;
+
+  // General matching routine.
+  // Match against text starting at offset startpos
+  // and stopping the search at offset endpos.
+  // Returns true if match found, false if not.
+  // On a successful match, fills in match[] (up to nmatch entries)
+  // with information about submatches.
+  // I.e. matching RE2("(foo)|(bar)baz") on "barbazbla" will return true,
+  // setting match[0] = "barbaz", match[1] = NULL, match[2] = "bar",
+  // match[3] = NULL, ..., up to match[nmatch-1] = NULL.
+  //
+  // Don't ask for more match information than you will use:
+  // runs much faster with nmatch == 1 than nmatch > 1, and
+  // runs even faster if nmatch == 0.
+  // Doesn't make sense to use nmatch > 1 + NumberOfCapturingGroups(),
+  // but will be handled correctly.
+  //
+  // Passing text == StringPiece(NULL, 0) will be handled like any other
+  // empty string, but note that on return, it will not be possible to tell
+  // whether submatch i matched the empty string or did not match:
+  // either way, match[i] == NULL.
+  bool Match(const StringPiece& text,
+             int startpos,
+             int endpos,
+             Anchor anchor,
+             StringPiece *match,
+             int nmatch) const;
+
+  // Check that the given rewrite string is suitable for use with this
+  // regular expression.  It checks that:
+  //   * The regular expression has enough parenthesized subexpressions
+  //     to satisfy all of the \N tokens in rewrite
+  //   * The rewrite string doesn't have any syntax errors.  E.g.,
+  //     '\' followed by anything other than a digit or '\'.
+  // A true return value guarantees that Replace() and Extract() won't
+  // fail because of a bad rewrite string.
+  bool CheckRewriteString(const StringPiece& rewrite, string* error) const;
+
+  // Constructor options
+  class Options {
+   public:
+    // The options are (defaults in parentheses):
+    //
+    //   utf8             (true)  text and pattern are UTF-8; otherwise Latin-1
+    //   posix_syntax     (false) restrict regexps to POSIX egrep syntax
+    //   longest_match    (false) search for longest match, not first match
+    //   log_errors       (true)  log syntax and execution errors to ERROR
+    //   max_mem          (see below)  approx. max memory footprint of RE2
+    //   literal          (false) interpret string as literal, not regexp
+    //   never_nl         (false) never match \n, even if it is in regexp
+    //   case_sensitive   (true)  match is case-sensitive (regexp can override
+    //                              with (?i) unless in posix_syntax mode)
+    //
+    // The following options are only consulted when posix_syntax == true.
+    // (When posix_syntax == false these features are always enabled and
+    // cannot be turned off.)
+    //   perl_classes     (false) allow Perl's \d \s \w \D \S \W
+    //   word_boundary    (false) allow Perl's \b \B (word boundary and not)
+    //   one_line         (false) ^ and $ only match beginning and end of text
+    //
+    // The max_mem option controls how much memory can be used
+    // to hold the compiled form of the regexp (the Prog) and
+    // its cached DFA graphs.  Code Search placed limits on the number
+    // of Prog instructions and DFA states: 10,000 for both.
+    // In RE2, those limits would translate to about 240 KB per Prog
+    // and perhaps 2.5 MB per DFA (DFA state sizes vary by regexp; RE2 does a
+    // better job of keeping them small than Code Search did).
+    // Each RE2 has two Progs (one forward, one reverse), and each Prog
+    // can have two DFAs (one first match, one longest match).
+    // That makes 4 DFAs:
+    //
+    //   forward, first-match    - used for UNANCHORED or ANCHOR_LEFT searches
+    //                               if opt.longest_match() == false
+    //   forward, longest-match  - used for all ANCHOR_BOTH searches,
+    //                               and the other two kinds if
+    //                               opt.longest_match() == true
+    //   reverse, first-match    - never used
+    //   reverse, longest-match  - used as second phase for unanchored searches
+    //
+    // The RE2 memory budget is statically divided between the two
+    // Progs and then the DFAs: two thirds to the forward Prog
+    // and one third to the reverse Prog.  The forward Prog gives half
+    // of what it has left over to each of its DFAs.  The reverse Prog
+    // gives it all to its longest-match DFA.
+    //
+    // Once a DFA fills its budget, it flushes its cache and starts over.
+    // If this happens too often, RE2 falls back on the NFA implementation.
+
+    enum Encoding {
+      EncodingUTF8 = 1,
+      EncodingLatin1
+    };
+
+    Options() :
+      encoding_(EncodingUTF8),
+      posix_syntax_(false),
+      longest_match_(false),
+      log_errors_(true),
+      max_mem_(kDefaultMaxMem),
+      literal_(false),
+      never_nl_(false),
+      case_sensitive_(true),
+      perl_classes_(false),
+      word_boundary_(false),
+      one_line_(false) {
+    }
+
+    Encoding encoding() const { return encoding_; }
+    void set_encoding(Encoding encoding) { encoding_ = encoding; }
+
+    // Legacy interface to encoding.
+    // TODO(rsc): Remove once clients have been converted.
+    bool utf8() const { return encoding_ == EncodingUTF8; }
+    void set_utf8(bool b) {
+      if (b) {
+        encoding_ = EncodingUTF8;
+      } else {
+        encoding_ = EncodingLatin1;
+      }
+    }
+
+    bool posix_syntax() const { return posix_syntax_; }
+    void set_posix_syntax(bool b) { posix_syntax_ = b; }
+
+    bool longest_match() const { return longest_match_; }
+    void set_longest_match(bool b) { longest_match_ = b; }
+
+    bool log_errors() const { return log_errors_; }
+    void set_log_errors(bool b) { log_errors_ = b; }
+
+    int max_mem() const { return max_mem_; }
+    void set_max_mem(int m) { max_mem_ = m; }
+
+    bool literal() const { return literal_; }
+    void set_literal(bool b) { literal_ = b; }
+
+    bool never_nl() const { return never_nl_; }
+    void set_never_nl(bool b) { never_nl_ = b; }
+
+    bool case_sensitive() const { return case_sensitive_; }
+    void set_case_sensitive(bool b) { case_sensitive_ = b; }
+
+    bool perl_classes() const { return perl_classes_; }
+    void set_perl_classes(bool b) { perl_classes_ = b; }
+
+    bool word_boundary() const { return word_boundary_; }
+    void set_word_boundary(bool b) { word_boundary_ = b; }
+
+    bool one_line() const { return one_line_; }
+    void set_one_line(bool b) { one_line_ = b; }
+
+    void Copy(const Options& src) {
+      encoding_ = src.encoding_;
+      posix_syntax_ = src.posix_syntax_;
+      longest_match_ = src.longest_match_;
+      log_errors_ = src.log_errors_;
+      max_mem_ = src.max_mem_;
+      literal_ = src.literal_;
+      never_nl_ = src.never_nl_;
+      case_sensitive_ = src.case_sensitive_;
+      perl_classes_ = src.perl_classes_;
+      word_boundary_ = src.word_boundary_;
+      one_line_ = src.one_line_;
+    }
+
+    int ParseFlags() const;
+
+   private:
+    // Private constructor for defining constants like RE2::Latin1.
+    friend class RE2;
+    Options(Encoding encoding,
+            bool posix_syntax,
+            bool longest_match,
+            bool log_errors) :
+      encoding_(encoding),
+      posix_syntax_(posix_syntax),
+      longest_match_(longest_match),
+      log_errors_(log_errors),
+      max_mem_(kDefaultMaxMem),
+      literal_(false),
+      never_nl_(false),
+      case_sensitive_(true),
+      perl_classes_(false),
+      word_boundary_(false),
+      one_line_(false) {
+    }
+
+    Encoding encoding_;
+    bool posix_syntax_;
+    bool longest_match_;
+    bool log_errors_;
+    int64_t max_mem_;
+    bool literal_;
+    bool never_nl_;
+    bool case_sensitive_;
+    bool perl_classes_;
+    bool word_boundary_;
+    bool one_line_;
+
+    //DISALLOW_EVIL_CONSTRUCTORS(Options);
+    Options(const Options&);
+    void operator=(const Options&);
+  };
+
+  // Returns the options set in the constructor.
+  const Options& options() const { return options_; };
+
+  // Argument converters; see below.
+  static inline Arg CRadix(short* x);
+  static inline Arg CRadix(unsigned short* x);
+  static inline Arg CRadix(int* x);
+  static inline Arg CRadix(unsigned int* x);
+  static inline Arg CRadix(long* x);
+  static inline Arg CRadix(unsigned long* x);
+  static inline Arg CRadix(long long* x);
+  static inline Arg CRadix(unsigned long long* x);
+
+  static inline Arg Hex(short* x);
+  static inline Arg Hex(unsigned short* x);
+  static inline Arg Hex(int* x);
+  static inline Arg Hex(unsigned int* x);
+  static inline Arg Hex(long* x);
+  static inline Arg Hex(unsigned long* x);
+  static inline Arg Hex(long long* x);
+  static inline Arg Hex(unsigned long long* x);
+
+  static inline Arg Octal(short* x);
+  static inline Arg Octal(unsigned short* x);
+  static inline Arg Octal(int* x);
+  static inline Arg Octal(unsigned int* x);
+  static inline Arg Octal(long* x);
+  static inline Arg Octal(unsigned long* x);
+  static inline Arg Octal(long long* x);
+  static inline Arg Octal(unsigned long long* x);
+
+ private:
+  void Init(const StringPiece& pattern, const Options& options);
+
+  bool Rewrite(string *out,
+               const StringPiece &rewrite,
+               const StringPiece* vec,
+               int veclen) const;
+
+  bool DoMatch(const StringPiece& text,
+                   Anchor anchor,
+                   int* consumed,
+                   const Arg* const args[],
+                   int n) const;
+
+  re2::Prog* ReverseProg() const;
+
+  mutable Mutex*           mutex_;
+  string                   pattern_;       // string regular expression
+  Options                  options_;       // option flags
+  string        prefix_;           // required prefix (before regexp_)
+  bool          prefix_foldcase_;  // prefix is ASCII case-insensitive
+  re2::Regexp*  entire_regexp_;    // parsed regular expression
+  re2::Regexp*  suffix_regexp_;    // parsed regular expression, prefix removed
+  re2::Prog*    prog_;             // compiled program for regexp
+  mutable re2::Prog* rprog_;       // reverse program for regexp
+  bool                     is_one_pass_;   // can use prog_->SearchOnePass?
+  mutable const string*    error_;         // Error indicator
+                                           // (or points to empty string)
+  mutable ErrorCode        error_code_;    // Error code
+  mutable string           error_arg_;     // Fragment of regexp showing error
+  mutable int              num_captures_;  // Number of capturing groups
+
+  // Map from capture names to indices
+  mutable const map<string, int>* named_groups_;
+
+  // Map from capture indices to names
+  mutable const map<int, string>* group_names_;
+
+  //DISALLOW_EVIL_CONSTRUCTORS(RE2);
+  RE2(const RE2&);
+  void operator=(const RE2&);
+};
+
+/***** Implementation details *****/
+
+// Hex/Octal/Binary?
+
+// Special class for parsing into objects that define a ParseFrom() method
+template <class T>
+class _RE2_MatchObject {
+ public:
+  static inline bool Parse(const char* str, int n, void* dest) {
+    if (dest == NULL) return true;
+    T* object = reinterpret_cast<T*>(dest);
+    return object->ParseFrom(str, n);
+  }
+};
+
+class RE2::Arg {
+ public:
+  // Empty constructor so we can declare arrays of RE2::Arg
+  Arg();
+
+  // Constructor specially designed for NULL arguments
+  Arg(void*);
+
+  typedef bool (*Parser)(const char* str, int n, void* dest);
+
+// Type-specific parsers
+#define MAKE_PARSER(type,name) \
+  Arg(type* p) : arg_(p), parser_(name) { } \
+  Arg(type* p, Parser parser) : arg_(p), parser_(parser) { } \
+
+
+  MAKE_PARSER(char,               parse_char);
+  MAKE_PARSER(signed char,        parse_char);
+  MAKE_PARSER(unsigned char,      parse_uchar);
+  MAKE_PARSER(short,              parse_short);
+  MAKE_PARSER(unsigned short,     parse_ushort);
+  MAKE_PARSER(int,                parse_int);
+  MAKE_PARSER(unsigned int,       parse_uint);
+  MAKE_PARSER(long,               parse_long);
+  MAKE_PARSER(unsigned long,      parse_ulong);
+  MAKE_PARSER(long long,          parse_longlong);
+  MAKE_PARSER(unsigned long long, parse_ulonglong);
+  MAKE_PARSER(float,              parse_float);
+  MAKE_PARSER(double,             parse_double);
+  MAKE_PARSER(string,             parse_string);
+  MAKE_PARSER(StringPiece,        parse_stringpiece);
+
+#undef MAKE_PARSER
+
+  // Generic constructor
+  template <class T> Arg(T*, Parser parser);
+  // Generic constructor template
+  template <class T> Arg(T* p)
+    : arg_(p), parser_(_RE2_MatchObject<T>::Parse) {
+  }
+
+  // Parse the data
+  bool Parse(const char* str, int n) const;
+
+ private:
+  void*         arg_;
+  Parser        parser_;
+
+  static bool parse_null          (const char* str, int n, void* dest);
+  static bool parse_char          (const char* str, int n, void* dest);
+  static bool parse_uchar         (const char* str, int n, void* dest);
+  static bool parse_float         (const char* str, int n, void* dest);
+  static bool parse_double        (const char* str, int n, void* dest);
+  static bool parse_string        (const char* str, int n, void* dest);
+  static bool parse_stringpiece   (const char* str, int n, void* dest);
+
+#define DECLARE_INTEGER_PARSER(name)                                        \
+ private:                                                                   \
+  static bool parse_ ## name(const char* str, int n, void* dest);           \
+  static bool parse_ ## name ## _radix(                                     \
+    const char* str, int n, void* dest, int radix);                         \
+ public:                                                                    \
+  static bool parse_ ## name ## _hex(const char* str, int n, void* dest);   \
+  static bool parse_ ## name ## _octal(const char* str, int n, void* dest); \
+  static bool parse_ ## name ## _cradix(const char* str, int n, void* dest)
+
+  DECLARE_INTEGER_PARSER(short);
+  DECLARE_INTEGER_PARSER(ushort);
+  DECLARE_INTEGER_PARSER(int);
+  DECLARE_INTEGER_PARSER(uint);
+  DECLARE_INTEGER_PARSER(long);
+  DECLARE_INTEGER_PARSER(ulong);
+  DECLARE_INTEGER_PARSER(longlong);
+  DECLARE_INTEGER_PARSER(ulonglong);
+
+#undef DECLARE_INTEGER_PARSER
+};
+
+inline RE2::Arg::Arg() : arg_(NULL), parser_(parse_null) { }
+inline RE2::Arg::Arg(void* p) : arg_(p), parser_(parse_null) { }
+
+inline bool RE2::Arg::Parse(const char* str, int n) const {
+  return (*parser_)(str, n, arg_);
+}
+
+// This part of the parser, appropriate only for ints, deals with bases
+#define MAKE_INTEGER_PARSER(type, name) \
+  inline RE2::Arg RE2::Hex(type* ptr) { \
+    return RE2::Arg(ptr, RE2::Arg::parse_ ## name ## _hex); } \
+  inline RE2::Arg RE2::Octal(type* ptr) { \
+    return RE2::Arg(ptr, RE2::Arg::parse_ ## name ## _octal); } \
+  inline RE2::Arg RE2::CRadix(type* ptr) { \
+    return RE2::Arg(ptr, RE2::Arg::parse_ ## name ## _cradix); }
+
+MAKE_INTEGER_PARSER(short,              short);
+MAKE_INTEGER_PARSER(unsigned short,     ushort);
+MAKE_INTEGER_PARSER(int,                int);
+MAKE_INTEGER_PARSER(unsigned int,       uint);
+MAKE_INTEGER_PARSER(long,               long);
+MAKE_INTEGER_PARSER(unsigned long,      ulong);
+MAKE_INTEGER_PARSER(long long,          longlong);
+MAKE_INTEGER_PARSER(unsigned long long, ulonglong);
+
+#undef MAKE_INTEGER_PARSER
+
+}  // namespace re2
+
+using re2::RE2;
+
+#endif /* RE2_RE2_H */