syntax_data: {"ast_node_type":"other","tokens":[{"end":43,"kind":"keyword","start":0,"text":"Some(CoroutineSavedLocal::new(idx))"}]}
source_snippet:         Some(CoroutineSavedLocal::new(idx))
context_before:         let idx = self.iter().take_while(|&l| l < local).count();
context_after:     }