syntax_data: {"ast_node_type":"other","tokens":[{"end":69,"kind":"keyword","start":0,"text":"p.pretty_print_const_valtree(cv,"}]}
source_snippet:                 p.pretty_print_const_valtree(cv, /*print_ty*/ true)?;
context_before:                 let mut p = FmtPrinter::new(tcx, Namespace::ValueNS);
context_after:                 f.write_str(&p.into_buffer())