diff --git a/mlir/docs/Tutorials/Toy/Ch-3.md b/mlir/docs/Tutorials/Toy/Ch-3.md
--- a/mlir/docs/Tutorials/Toy/Ch-3.md
+++ b/mlir/docs/Tutorials/Toy/Ch-3.md
@@ -94,12 +94,13 @@
     TransposeOp transposeInputOp =
         llvm::dyn_cast_or_null<TransposeOp>(transposeInput.getDefiningOp());
     // If the input is defined by another Transpose, bingo!
-    if (!transposeInputOp)
+    if (transposeInputOp) {
+      // Use the rewriter to perform the replacement.
+      rewriter.replaceOp(op, {transposeInputOp.getOperand()}, {transposeInputOp});
+      return matchSuccess();
+    } else {
       return matchFailure();
-
-    // Use the rewriter to perform the replacement
-    rewriter.replaceOp(op, {transposeInputOp.getOperand()}, {transposeInputOp});
-    return matchSuccess();
+    }
   }
 };
 ```
diff --git a/mlir/examples/toy/Ch3/mlir/ToyCombine.cpp b/mlir/examples/toy/Ch3/mlir/ToyCombine.cpp
--- a/mlir/examples/toy/Ch3/mlir/ToyCombine.cpp
+++ b/mlir/examples/toy/Ch3/mlir/ToyCombine.cpp
@@ -44,12 +44,13 @@
         llvm::dyn_cast_or_null<TransposeOp>(transposeInput.getDefiningOp());
 
     // If the input is defined by another Transpose, bingo!
-    if (!transposeInputOp)
+    if (transposeInputOp) {
+      // Use the rewriter to perform the replacement.
+      rewriter.replaceOp(op, {transposeInputOp.getOperand()}, {transposeInputOp});
+      return matchSuccess();
+    } else {
       return matchFailure();
-
-    // Use the rewriter to perform the replacement.
-    rewriter.replaceOp(op, {transposeInputOp.getOperand()});
-    return matchSuccess();
+    }
   }
 };
 
diff --git a/mlir/examples/toy/Ch4/mlir/ToyCombine.cpp b/mlir/examples/toy/Ch4/mlir/ToyCombine.cpp
--- a/mlir/examples/toy/Ch4/mlir/ToyCombine.cpp
+++ b/mlir/examples/toy/Ch4/mlir/ToyCombine.cpp
@@ -49,12 +49,13 @@
         llvm::dyn_cast_or_null<TransposeOp>(transposeInput.getDefiningOp());
 
     // If the input is defined by another Transpose, bingo!
-    if (!transposeInputOp)
+    if (transposeInputOp) {
+      // Use the rewriter to perform the replacement.
+      rewriter.replaceOp(op, {transposeInputOp.getOperand()}, {transposeInputOp});
+      return matchSuccess();
+    } else {
       return matchFailure();
-
-    // Use the rewriter to perform the replacement.
-    rewriter.replaceOp(op, {transposeInputOp.getOperand()});
-    return matchSuccess();
+    }
   }
 };
 
diff --git a/mlir/examples/toy/Ch5/mlir/ToyCombine.cpp b/mlir/examples/toy/Ch5/mlir/ToyCombine.cpp
--- a/mlir/examples/toy/Ch5/mlir/ToyCombine.cpp
+++ b/mlir/examples/toy/Ch5/mlir/ToyCombine.cpp
@@ -49,12 +49,13 @@
         llvm::dyn_cast_or_null<TransposeOp>(transposeInput.getDefiningOp());
 
     // If the input is defined by another Transpose, bingo!
-    if (!transposeInputOp)
+    if (transposeInputOp) {
+      // Use the rewriter to perform the replacement.
+      rewriter.replaceOp(op, {transposeInputOp.getOperand()}, {transposeInputOp});
+      return matchSuccess();
+    } else {
       return matchFailure();
-
-    // Use the rewriter to perform the replacement.
-    rewriter.replaceOp(op, {transposeInputOp.getOperand()});
-    return matchSuccess();
+    }
   }
 };
 
diff --git a/mlir/examples/toy/Ch6/mlir/ToyCombine.cpp b/mlir/examples/toy/Ch6/mlir/ToyCombine.cpp
--- a/mlir/examples/toy/Ch6/mlir/ToyCombine.cpp
+++ b/mlir/examples/toy/Ch6/mlir/ToyCombine.cpp
@@ -49,12 +49,13 @@
         llvm::dyn_cast_or_null<TransposeOp>(transposeInput.getDefiningOp());
 
     // If the input is defined by another Transpose, bingo!
-    if (!transposeInputOp)
+    if (transposeInputOp) {
+      // Use the rewriter to perform the replacement.
+      rewriter.replaceOp(op, {transposeInputOp.getOperand()}, {transposeInputOp});
+      return matchSuccess();
+    } else {
       return matchFailure();
-
-    // Use the rewriter to perform the replacement.
-    rewriter.replaceOp(op, {transposeInputOp.getOperand()});
-    return matchSuccess();
+    }
   }
 };
 
diff --git a/mlir/examples/toy/Ch7/mlir/ToyCombine.cpp b/mlir/examples/toy/Ch7/mlir/ToyCombine.cpp
--- a/mlir/examples/toy/Ch7/mlir/ToyCombine.cpp
+++ b/mlir/examples/toy/Ch7/mlir/ToyCombine.cpp
@@ -67,12 +67,13 @@
         llvm::dyn_cast_or_null<TransposeOp>(transposeInput.getDefiningOp());
 
     // If the input is defined by another Transpose, bingo!
-    if (!transposeInputOp)
+    if (transposeInputOp) {
+      // Use the rewriter to perform the replacement.
+      rewriter.replaceOp(op, {transposeInputOp.getOperand()}, {transposeInputOp});
+      return matchSuccess();
+    } else {
       return matchFailure();
-
-    // Use the rewriter to perform the replacement.
-    rewriter.replaceOp(op, {transposeInputOp.getOperand()});
-    return matchSuccess();
+    }
   }
 };