X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FSupport%2FRegex.h;h=82df2c67bd027eb22d8f37de943766c0920970c9;hb=a5bf44b0b396e8b9ae0db5c62c05ac6618aab5d3;hp=0bf253f4c19208887b2ac89606e4f321dc4efe5e;hpb=528700863adefca8de461ce28a7d903729fb96b4;p=oota-llvm.git

diff --git a/include/llvm/Support/Regex.h b/include/llvm/Support/Regex.h
index 0bf253f4c19..82df2c67bd0 100644
--- a/include/llvm/Support/Regex.h
+++ b/include/llvm/Support/Regex.h
@@ -7,10 +7,16 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// This file implements a POSIX regular expression matcher.
+// This file implements a POSIX regular expression matcher.  Both Basic and
+// Extended POSIX regular expressions (ERE) are supported.  EREs were extended
+// to support backreferences in matches.
+// This implementation also supports matching strings with embedded NUL chars.
 //
 //===----------------------------------------------------------------------===//
 
+#ifndef LLVM_SUPPORT_REGEX_H
+#define LLVM_SUPPORT_REGEX_H
+
 #include <string>
 
 struct llvm_regex;
@@ -18,51 +24,63 @@ struct llvm_regex;
 namespace llvm {
   class StringRef;
   template<typename T> class SmallVectorImpl;
-  
+
   class Regex {
   public:
     enum {
-      /// Compile with support for subgroup matches, this is just to make
-      /// constructs like Regex("...", 0) more readable as Regex("...", Sub).
-      Sub=0,
+      NoFlags=0,
       /// Compile for matching that ignores upper/lower case distinctions.
       IgnoreCase=1,
-      /// Compile for matching that need only report success or failure,
-      /// not what was matched.
-      NoSub=2,
       /// Compile for newline-sensitive matching. With this flag '[^' bracket
-      /// expressions and '.' never match newline. A ^ anchor matches the 
-      /// null string after any newline in the string in addition to its normal 
-      /// function, and the $ anchor matches the null string before any 
+      /// expressions and '.' never match newline. A ^ anchor matches the
+      /// null string after any newline in the string in addition to its normal
+      /// function, and the $ anchor matches the null string before any
       /// newline in the string in addition to its normal function.
-      Newline=4
+      Newline=2,
+      /// By default, the POSIX extended regular expression (ERE) syntax is
+      /// assumed. Pass this flag to turn on basic regular expressions (BRE)
+      /// instead.
+      BasicRegex=4
     };
 
-    /// Compiles the given POSIX Extended Regular Expression \arg Regex.
-    /// This implementation supports regexes and matching strings with embedded
-    /// NUL characters.
-    Regex(const StringRef &Regex, unsigned Flags=NoSub);
+    /// Compiles the given regular expression \p Regex.
+    Regex(StringRef Regex, unsigned Flags = NoFlags);
     ~Regex();
 
     /// isValid - returns the error encountered during regex compilation, or
     /// matching, if any.
     bool isValid(std::string &Error);
 
-    /// matches - Match the regex against a given \arg String.
+    /// getNumMatches - In a valid regex, return the number of parenthesized
+    /// matches it contains.  The number filled in by match will include this
+    /// many entries plus one for the whole regex (as element 0).
+    unsigned getNumMatches() const;
+
+    /// matches - Match the regex against a given \p String.
     ///
-    /// \param Matches - If given, on a succesful match this will be filled in
-    /// with references to the matched group expressions (inside \arg String),
+    /// \param Matches - If given, on a successful match this will be filled in
+    /// with references to the matched group expressions (inside \p String),
     /// the first group is always the entire pattern.
-    /// By default the regex is compiled with NoSub, which disables support for
-    /// Matches.
-    /// For this feature to be enabled you must construct the regex using
-    /// Regex("...", Regex::Sub) constructor.
     ///
     /// This returns true on a successful match.
-    bool match(const StringRef &String, SmallVectorImpl<StringRef> *Matches=0);
+    bool match(StringRef String, SmallVectorImpl<StringRef> *Matches = 0);
+
+    /// sub - Return the result of replacing the first match of the regex in
+    /// \p String with the \p Repl string. Backreferences like "\0" in the
+    /// replacement string are replaced with the appropriate match substring.
+    ///
+    /// Note that the replacement string has backslash escaping performed on
+    /// it. Invalid backreferences are ignored (replaced by empty strings).
+    ///
+    /// \param Error If non-null, any errors in the substitution (invalid
+    /// backreferences, trailing backslashes) will be recorded as a non-empty
+    /// string.
+    std::string sub(StringRef Repl, StringRef String, std::string *Error = 0);
+
   private:
     struct llvm_regex *preg;
     int error;
-    bool sub;
   };
 }
+
+#endif // LLVM_SUPPORT_REGEX_H