[Support/StringRef] Add find_last_not_of and {r,l,}trim.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156652 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 22 insertions, 0 deletions

diff --git a/include/llvm/ADT/StringRef.h b/include/llvm/ADT/StringRef.h
index 76ba66e..b548568 100644
--- a/include/llvm/ADT/StringRef.h
+++ b/include/llvm/ADT/StringRef.h
@@ -292,6 +292,16 @@ namespace llvm {
     /// Note: O(size() + Chars.size())
     size_type find_last_of(StringRef Chars, size_t From = npos) const;
 
+    /// find_last_not_of - Find the last character in the string that is not
+    /// \arg C, or npos if not found.
+    size_type find_last_not_of(char C, size_t From = npos) const;
+
+    /// find_last_not_of - Find the last character in the string that is not in
+    /// \arg Chars, or npos if not found.
+    ///
+    /// Note: O(size() + Chars.size())
+    size_type find_last_not_of(StringRef Chars, size_t From = npos) const;
+
     /// @}
     /// @name Helpful Algorithms
     /// @{
@@ -480,6 +490,18 @@ namespace llvm {
       return std::make_pair(slice(0, Idx), slice(Idx+1, npos));
     }
 
+    StringRef ltrim(StringRef Chars = " \t\n\v\f\r") const {
+      return drop_front(std::min(Length, find_first_not_of(Chars)));
+    }
+
+    StringRef rtrim(StringRef Chars = " \t\n\v\f\r") const {
+      return drop_back(Length - std::min(Length, find_last_not_of(Chars) + 1));
+    }
+
+    StringRef trim(StringRef Chars = " \t\n\v\f\r") const {
+      return ltrim(Chars).rtrim(Chars);
+    }
+
     /// @}
   };