syntax_data: {"ast_node_type":"other","tokens":[{"end":54,"kind":"keyword","start":0,"text":"FloatVar(_)"}]}
source_snippet:             FloatVar(_) => write!(f, "{}", "{float}"),
context_before:             IntVar(_) => write!(f, "{}", "{integer}"),
context_after:             FreshTy(v) => write!(f, "FreshTy({v})"),