syntax_data: {"ast_node_type":"other","tokens":[{"end":46,"kind":"keyword","start":0,"text":"offset.map(|offset|"}]}
source_snippet:                 offset.map(|offset| Instance {
context_before:                     .position(|def_id| def_id == trait_item_id);
context_after:                     def: ty::InstanceKind::Virtual(trait_item_id, vtable_base + offset),