Fix `Analysis` example
diff --git a/src/librustc_mir/dataflow/generic.rs b/src/librustc_mir/dataflow/generic.rs
index 47d6bd9..73f17e7 100644
--- a/src/librustc_mir/dataflow/generic.rs
+++ b/src/librustc_mir/dataflow/generic.rs
@@ -23,11 +23,13 @@
///
/// ```ignore(cross-crate-imports)
/// fn do_my_analysis(body: &mir::Body<'tcx>, dead_unwinds: &BitSet<BasicBlock>) {
+/// // `MyAnalysis` implements `Analysis`.
/// let analysis = MyAnalysis::new();
-/// let results = Engine::new(body, dead_unwinds, analysis).iterate_to_fixpoint();
-/// let mut cursor = dataflow::ResultsCursor::new(body, results);
///
-/// for statement_index in body.block_data[START_BLOCK].statements.iter() {
+/// let results = Engine::new(body, dead_unwinds, analysis).iterate_to_fixpoint();
+/// let mut cursor = ResultsCursor::new(body, results);
+///
+/// for (_, statement_index) in body.block_data[START_BLOCK].statements.iter_enumerated() {
/// cursor.seek_after(Location { block: START_BLOCK, statement_index });
/// let state = cursor.get();
/// println!("{:?}", state);
