syntax_data: {"ast_node_type":"variable","tokens":[{"end":90,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:                 let overflow_err = AssertKind::Overflow(op, lhs.to_copy(), rhs.to_copy());
context_after:                 block = self.assert(block, Operand::Move(inbounds), true, overflow_err, span);