syntax_data: {"ast_node_type":"other","tokens":[{"end":90,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // If any upvars are moved out of, drop elaboration will handle upvar destruction.
context_before:         // Expand `drop(coroutine_struct)` to a drop ladder which destroys upvars.
context_after:         // However we need to also elaborate the code generated by `insert_clean_drop`.