[llvm] r363617 - Add convenience utility for replacing a range within a container with a

[Richard Smith via llvm-commits]

Author: rsmith
Date: Mon Jun 17 14:01:09 2019
New Revision: 363617

URL: http://llvm.org/viewvc/llvm-project?rev=363617&view=rev
Log:
Add convenience utility for replacing a range within a container with a
different range, in preparation for use in Clang.

Modified:
    llvm/trunk/include/llvm/ADT/STLExtras.h

Modified: llvm/trunk/include/llvm/ADT/STLExtras.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/STLExtras.h?rev=363617&r1=363616&r2=363617&view=diff
==============================================================================
--- llvm/trunk/include/llvm/ADT/STLExtras.h (original)
+++ llvm/trunk/include/llvm/ADT/STLExtras.h Mon Jun 17 14:01:09 2019
@@ -1392,6 +1392,33 @@ void erase_if(Container &C, UnaryPredica
   C.erase(remove_if(C, P), C.end());
 }
 
+/// Given a sequence container Cont, replace the range [ContIt, ContEnd) with
+/// the range [ValIt, ValEnd) (which is not from the same container).
+template<typename Container, typename RandomAccessIterator>
+void replace(Container &Cont, typename Container::iterator ContIt,
+             typename Container::iterator ContEnd, RandomAccessIterator ValIt,
+             RandomAccessIterator ValEnd) {
+  while (true) {
+    if (ValIt == ValEnd) {
+      Cont.erase(ContIt, ContEnd);
+      return;
+    } else if (ContIt == ContEnd) {
+      Cont.insert(ContIt, ValIt, ValEnd);
+      return;
+    }
+    *ContIt++ = *ValIt++;
+  }
+}
+
+/// Given a sequence container Cont, replace the range [ContIt, ContEnd) with
+/// the range R.
+template<typename Container, typename Range = std::initializer_list<
+                                 typename Container::value_type>>
+void replace(Container &Cont, typename Container::iterator ContIt,
+             typename Container::iterator ContEnd, Range R) {
+  replace(Cont, ContIt, ContEnd, R.begin(), R.end());
+}
+
 //===----------------------------------------------------------------------===//
 //     Extra additions to <memory>
 //===----------------------------------------------------------------------===//