return
		}
	}

	// just an ordinary function
	r.funcs.set(fun, r.mode&PreserveAST != 0)
}

// lookupTypeParam searches for type parameters named name within the tparams
// field list, returning the relevant identifier if found, or nil if not.
func lookupTypeParam(name string, tparams *ast.FieldList) *ast.Ident {
	if tparams == nil {
		return nil
	}
	for _, field := range tparams.List {