The table in Combining Operations implies that the attribute of (int_ % ',') | attr(std::vector<int>{}) would be std::variant<std::vector<int>, std::vector<int>>. But it isn't due to special rules. While these special rules are described in Parser attributes, we cannot see them from the Table 1.2. (Combining Operations and Their Semantics)
The table in Combining Operations implies that the attribute of
(int_ % ',') | attr(std::vector<int>{})
would bestd::variant<std::vector<int>, std::vector<int>>
. But it isn't due to special rules. While these special rules are described in Parser attributes, we cannot see them from the Table 1.2. (Combining Operations and Their Semantics)