[Mlir-commits] [mlir] [MLIR][Python] Improve Iterator performance. Don't `throw` in `dunderNext` methods. (PR #175377)

[Maksim Levental]

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@@ -194,13 +194,14 @@ nb::object PyBlock::getCapsule() {
 // Collections.
 //------------------------------------------------------------------------------
 
-PyRegion PyRegionIterator::dunderNext() {
+nb::typed<nb::object, PyRegion> PyRegionIterator::dunderNext() {
   operation->checkValid();
   if (nextIndex >= mlirOperationGetNumRegions(operation->get())) {
-    throw nb::stop_iteration();
+    PyErr_SetNone(PyExc_StopIteration);
+    return nb::object();
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makslevental wrote:

i.e. return `std::nullopt` here

https://github.com/llvm/llvm-project/pull/175377