Wei-Ming Yang a3b5ce8a93 improve aux::arg_list<>::operator[]() ...

Add the assert to avoid ugly message when invoked `arg_list<>::operator[](lazy_default<>)` with `maybe<>`

2016-11-23 09:53:54 +08:00

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boost

improve aux::arg_list<>::operator[]()

2016-11-23 09:53:54 +08:00