Tuples in argument lists

[kaandocal]

The following is a valid Julia function:
(a, (b, d), e) -> d + e
but doesn't work with RuntimeGeneratedFunctions (normalize_args throws an error). I've tried adding an override for :tuple that returns Tuple(normalize_args.(expr.args)) but then the new function throws an error:
TypeError: in Type, in parameter, expected Type, got a value of type Tuple{Symbol, Tuple{Symbol, Symbol}, Symbol}