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Subject: [boost] [spirit-x3]What's use case for x3::variant<OnlyOneComponent>?
From: Larry Evans (cppljevans_at_[hidden])
Date: 2018-01-28 22:17:57


doesn't mention a unary variant:


and the comments in:

indicates variant<T> is collapsed to T, why isn't the x3::variant here:

declared as:

   template <typename L, typename R, typename ...Types>
   struct variant

instead of:

   template <typename ...Types>
   struct variant

which allows sizeof...(Types)==0 instead of the minimum
size of 2? That would disallow the primary and factor
using's here:

which make no sense because, for example, primary_def is *not*
an alternative parser.


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