diff --git a/mlir/include/mlir/Dialect/MemRef/IR/MemRef.h b/mlir/include/mlir/Dialect/MemRef/IR/MemRef.h
--- a/mlir/include/mlir/Dialect/MemRef/IR/MemRef.h
+++ b/mlir/include/mlir/Dialect/MemRef/IR/MemRef.h
@@ -24,7 +24,7 @@
 class Location;
 class OpBuilder;
 
-raw_ostream &operator<<(raw_ostream &os, Range &range);
+raw_ostream &operator<<(raw_ostream &os, const Range &range);
 
 /// Return the list of Range (i.e. offset, size, stride). Each Range
 /// entry contains either the dynamic value or a ConstantIndexOp constructed
diff --git a/mlir/include/mlir/IR/OpDefinition.h b/mlir/include/mlir/IR/OpDefinition.h
--- a/mlir/include/mlir/IR/OpDefinition.h
+++ b/mlir/include/mlir/IR/OpDefinition.h
@@ -109,11 +109,11 @@
   MLIRContext *getContext() { return getOperation()->getContext(); }
 
   /// Print the operation to the given stream.
-  void print(raw_ostream &os, OpPrintingFlags flags = llvm::None) {
+  void print(raw_ostream &os, OpPrintingFlags flags = llvm::None) const {
     state->print(os, flags);
   }
   void print(raw_ostream &os, AsmState &asmState,
-             OpPrintingFlags flags = llvm::None) {
+             OpPrintingFlags flags = llvm::None) const {
     state->print(os, asmState, flags);
   }
 
@@ -222,7 +222,7 @@
 }
 
 /// Allow printing to a stream.
-inline raw_ostream &operator<<(raw_ostream &os, OpState &op) {
+inline raw_ostream &operator<<(raw_ostream &os, const OpState &op) {
   op.print(os, OpPrintingFlags().useLocalScope());
   return os;
 }
@@ -1647,9 +1647,9 @@
       llvm::is_detected<has_single_result_fold, T>;
   /// Trait to check if T provides a general 'fold' method.
   template <typename T, typename... Args>
-  using has_fold = decltype(std::declval<T>().fold(
-      std::declval<ArrayRef<Attribute>>(),
-      std::declval<SmallVectorImpl<OpFoldResult> &>()));
+  using has_fold = decltype(
+      std::declval<T>().fold(std::declval<ArrayRef<Attribute>>(),
+                             std::declval<SmallVectorImpl<OpFoldResult> &>()));
   template <typename T>
   using detect_has_fold = llvm::is_detected<has_fold, T>;
   /// Trait to check if T provides a 'print' method.
diff --git a/mlir/include/mlir/IR/Operation.h b/mlir/include/mlir/IR/Operation.h
--- a/mlir/include/mlir/IR/Operation.h
+++ b/mlir/include/mlir/IR/Operation.h
@@ -117,7 +117,8 @@
   Operation *getParentOp() { return block ? block->getParentOp() : nullptr; }
 
   /// Return the closest surrounding parent operation that is of type 'OpTy'.
-  template <typename OpTy> OpTy getParentOfType() {
+  template <typename OpTy>
+  OpTy getParentOfType() {
     auto *op = this;
     while ((op = op->getParentOp()))
       if (auto parentOp = dyn_cast<OpTy>(op))
@@ -331,10 +332,12 @@
   Attribute getAttr(Identifier name) { return attrs.get(name); }
   Attribute getAttr(StringRef name) { return attrs.get(name); }
 
-  template <typename AttrClass> AttrClass getAttrOfType(Identifier name) {
+  template <typename AttrClass>
+  AttrClass getAttrOfType(Identifier name) {
     return getAttr(name).dyn_cast_or_null<AttrClass>();
   }
-  template <typename AttrClass> AttrClass getAttrOfType(StringRef name) {
+  template <typename AttrClass>
+  AttrClass getAttrOfType(StringRef name) {
     return getAttr(name).dyn_cast_or_null<AttrClass>();
   }
 
@@ -473,7 +476,8 @@
 
   /// Returns true if the operation was registered with a particular trait, e.g.
   /// hasTrait<OperandsAreSignlessIntegerLike>().
-  template <template <typename T> class Trait> bool hasTrait() {
+  template <template <typename T> class Trait>
+  bool hasTrait() {
     const AbstractOperation *abstractOp = getAbstractOperation();
     return abstractOp ? abstractOp->hasTrait<Trait>() : false;
   }
@@ -481,7 +485,8 @@
   /// Returns true if the operation is *might* have the provided trait. This
   /// means that either the operation is unregistered, or it was registered with
   /// the provide trait.
-  template <template <typename T> class Trait> bool mightHaveTrait() {
+  template <template <typename T> class Trait>
+  bool mightHaveTrait() {
     const AbstractOperation *abstractOp = getAbstractOperation();
     return abstractOp ? abstractOp->hasTrait<Trait>() : true;
   }
@@ -717,8 +722,8 @@
   size_t numTrailingObjects(OverloadToken<Region>) const { return numRegions; }
 };
 
-inline raw_ostream &operator<<(raw_ostream &os, Operation &op) {
-  op.print(os, OpPrintingFlags().useLocalScope());
+inline raw_ostream &operator<<(raw_ostream &os, const Operation &op) {
+  const_cast<Operation &>(op).print(os, OpPrintingFlags().useLocalScope());
   return os;
 }
 
@@ -726,7 +731,8 @@
 
 namespace llvm {
 /// Provide isa functionality for operation casts.
-template <typename T> struct isa_impl<T, ::mlir::Operation> {
+template <typename T>
+struct isa_impl<T, ::mlir::Operation> {
   static inline bool doit(const ::mlir::Operation &op) {
     return T::classof(const_cast<::mlir::Operation *>(&op));
   }
@@ -734,10 +740,12 @@
 
 /// Provide specializations for operation casts as the resulting T is value
 /// typed.
-template <typename T> struct cast_retty_impl<T, ::mlir::Operation *> {
+template <typename T>
+struct cast_retty_impl<T, ::mlir::Operation *> {
   using ret_type = T;
 };
-template <typename T> struct cast_retty_impl<T, ::mlir::Operation> {
+template <typename T>
+struct cast_retty_impl<T, ::mlir::Operation> {
   using ret_type = T;
 };
 template <class T>
diff --git a/mlir/lib/Dialect/MemRef/IR/MemRefOps.cpp b/mlir/lib/Dialect/MemRef/IR/MemRefOps.cpp
--- a/mlir/lib/Dialect/MemRef/IR/MemRefOps.cpp
+++ b/mlir/lib/Dialect/MemRef/IR/MemRefOps.cpp
@@ -2066,7 +2066,7 @@
   return produceSubViewErrorMsg(result, op, expectedType, errMsg);
 }
 
-raw_ostream &mlir::operator<<(raw_ostream &os, Range &range) {
+raw_ostream &mlir::operator<<(raw_ostream &os, const Range &range) {
   return os << "range " << range.offset << ":" << range.size << ":"
             << range.stride;
 }
diff --git a/mlir/unittests/IR/OperationSupportTest.cpp b/mlir/unittests/IR/OperationSupportTest.cpp
--- a/mlir/unittests/IR/OperationSupportTest.cpp
+++ b/mlir/unittests/IR/OperationSupportTest.cpp
@@ -10,6 +10,7 @@
 #include "mlir/IR/Builders.h"
 #include "mlir/IR/BuiltinTypes.h"
 #include "llvm/ADT/BitVector.h"
+#include "llvm/Support/FormatVariadic.h"
 #include "gtest/gtest.h"
 
 using namespace mlir;
@@ -214,4 +215,14 @@
   containerOp->destroy();
 }
 
+TEST(OperationFormatPrintTest, CanUseVariadicFormat) {
+  MLIRContext context;
+  Builder builder(&context);
+
+  Operation *op = createOp(&context);
+
+  std::string str = formatv("{0}", *op).str();
+  ASSERT_STREQ(str.c_str(), "\"foo.bar\"() : () -> ()");
+}
+
 } // end namespace