1 //===-- Regex.h - Regular Expression matcher implementation -*- C++ -*-----===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements a POSIX regular expression matcher. Both Basic and
11 // Extended POSIX regular expressions (ERE) are supported. EREs were extended
12 // to support backreferences in matches.
13 // This implementation also supports matching strings with embedded NUL chars.
15 //===----------------------------------------------------------------------===//
17 #ifndef LLVM_SUPPORT_REGEX_H
18 #define LLVM_SUPPORT_REGEX_H
26 template<typename T> class SmallVectorImpl;
32 /// Compile for matching that ignores upper/lower case distinctions.
34 /// Compile for newline-sensitive matching. With this flag '[^' bracket
35 /// expressions and '.' never match newline. A ^ anchor matches the
36 /// null string after any newline in the string in addition to its normal
37 /// function, and the $ anchor matches the null string before any
38 /// newline in the string in addition to its normal function.
40 /// By default, the POSIX extended regular expression (ERE) syntax is
41 /// assumed. Pass this flag to turn on basic regular expressions (BRE)
46 /// Compiles the given regular expression \p Regex.
47 Regex(StringRef Regex, unsigned Flags = NoFlags);
50 /// isValid - returns the error encountered during regex compilation, or
52 bool isValid(std::string &Error);
54 /// getNumMatches - In a valid regex, return the number of parenthesized
55 /// matches it contains. The number filled in by match will include this
56 /// many entries plus one for the whole regex (as element 0).
57 unsigned getNumMatches() const;
59 /// matches - Match the regex against a given \p String.
61 /// \param Matches - If given, on a successful match this will be filled in
62 /// with references to the matched group expressions (inside \p String),
63 /// the first group is always the entire pattern.
65 /// This returns true on a successful match.
66 bool match(StringRef String, SmallVectorImpl<StringRef> *Matches = 0);
68 /// sub - Return the result of replacing the first match of the regex in
69 /// \p String with the \p Repl string. Backreferences like "\0" in the
70 /// replacement string are replaced with the appropriate match substring.
72 /// Note that the replacement string has backslash escaping performed on
73 /// it. Invalid backreferences are ignored (replaced by empty strings).
75 /// \param Error If non-null, any errors in the substitution (invalid
76 /// backreferences, trailing backslashes) will be recorded as a non-empty
78 std::string sub(StringRef Repl, StringRef String, std::string *Error = 0);
81 struct llvm_regex *preg;
86 #endif // LLVM_SUPPORT_REGEX_H