syntax_data: {"ast_node_type":"function","tokens":[{"end":67,"kind":"keyword","start":0,"text":"fn"}]}
source_snippet:                 fn try_fold_with<F: $crate::FallibleTypeFolder<I>>(
context_before:             impl<I: $crate::Interner> $crate::TypeFoldable<I> for $ty {
context_after:                     self,