syntax_data: {"ast_node_type":"function","tokens":[{"end":46,"kind":"keyword","start":0,"text":"pub"}]}
source_snippet:     pub fn in_derive_expansion(self) -> bool {
context_before:     /// Returns `true` if `span` originates in a derive-macro's expansion.
context_after:         matches!(self.ctxt().outer_expn_data().kind, ExpnKind::Macro(MacroKind::Derive, _))