Proposed resolution:

This wording is relative to N4713 after an editorial edit.

1. Modify [variant.visit] as indicated:

   template<class Visitor, class... Variants>
     constexpr see below visit(Visitor&& vis, Variants&&... vars);
   

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   -3- Returns: e(m), where m is the pack for which m_i is vars_i.index() for all 0 <= i < n. The return type is the type of e(m)decltype(e(m)).

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