syntax_data: {"ast_node_type":"other","tokens":[{"end":57,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                 // FIXME: pass a proper `opt_match_place`
context_before:             ExprKind::Let { expr: _, pat: ref guard_pat } => {
context_after:                 self.declare_bindings(visibility_scope, scope_span, guard_pat, None, None);