shamalgs::HasCustomDefaults Concept Reference

Detects whether Alt opts into exposing more than one default instance of itself (e.g. the same alternative with different tunable field values) via a static variant_custom_defaults() method, for example: More...

#include <shamalgs/include/shamalgs/ImplVariant.hpp>

Concept definition

template<class Alt>
concept shamalgs::HasCustomDefaults =  requires {
        { Alt::variant_custom_defaults() } -> std::convertible_to<std::vector<Alt>>;
    }

Detailed Description

Detects whether Alt opts into exposing more than one default instance of itself (e.g. the same alternative with different tunable field values) via a static variant_custom_defaults() method, for example:

struct GpuTeamFetching {
    static constexpr std::string_view variant_type_name = "gpu_team_fetching";
    u32 group_size = 128;
 
    static std::vector<GpuTeamFetching> variant_custom_defaults() {
        return {GpuTeamFetching{128}, GpuTeamFetching{256}};
    }
};

Alternatives that do not define it (the common case) keep exposing exactly one, default-constructed instance.

Definition at line 111 of file ImplVariant.hpp.