syntax_data: {"ast_node_type":"variable","tokens":[{"end":97,"kind":"keyword","start":0,"text":"self.tcx.dcx().span_bug(expr_span,"}]}
source_snippet:                 self.tcx.dcx().span_bug(expr_span, "let expression not expected in this context")
context_before:             DeclareLetBindings::LetNotPermitted => {
context_after:             }