syntax_data: {"ast_node_type":"other","tokens":[{"end":54,"kind":"keyword","start":0,"text":"|(dst_ref,"}]}
source_snippet:                         |(dst_ref, dst_state_prime)| {
context_before:                     Quantifier::ThereExists.apply(self.dst.refs_from(dst_state).map(
context_after:                             if !src_ref.is_mut && dst_ref.is_mut {