Boost C++ Libraries

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grammar::is_rule

Determine if T meets the requirements of Rule.

Synopsis

Defined in header <boost/url/grammar/type_traits.hpp>

template<
    class T>
using is_rule = see-below;

Description

This is an alias for std::true_type if T meets the requirements, otherwise it is an alias for std::false_type.

Example

struct U
{
    struct value_type;

    auto
    parse(
        char const*& it,
        char const* end) const ->
            result<value_type>
};

static_assert( is_rule<U>::value, "Requirements not met" );

See Also

Convenience header <boost/url/grammar.hpp>