1+++ 2title = "`static bool _has_error_is_errno(Impl &&) noexcept`" 3description = "Returns true if the error code in the implementation passed in has a domain or category matching that of POSIX `errno`. Constexpr, never throws." 4categories = ["observers"] 5weight = 240 6+++ 7 8Returns true if the error code in the implementation passed in has a domain or category matching that of POSIX `errno`. Constexpr where possible. 9 10*Requires*: Always available. 11 12*Complexity*: Constant time. 13 14*Guarantees*: Never throws an exception. 15