Platform_Extensions.VK_KHR_PORTABILITY_SUBSET_SPEC_VERSION

Undocumented in source but is binding to an external library. You might be able to learn more by searching the web for its name.
mixintemplate Platform_Extensions(extensions...)
extern (System) nothrow @nogc
static if(!(__traits(isSame, extension, KHR_xlib_surface)))
static if(!(__traits(isSame, extension, KHR_xcb_surface)))
static if(!(__traits(isSame, extension, KHR_wayland_surface)))
static if(!(__traits(isSame, extension, KHR_android_surface)))
static if(!(__traits(isSame, extension, KHR_win32_surface)))
static if(!(__traits(isSame, extension, KHR_video_queue)))
static if(!(__traits(isSame, extension, KHR_video_decode_queue)))
static if(!(__traits(isSame, extension, KHR_external_memory_win32)))
static if(!(__traits(isSame, extension, KHR_win32_keyed_mutex)))
static if(!(__traits(isSame, extension, KHR_external_semaphore_win32)))
static if(!(__traits(isSame, extension, KHR_external_fence_win32)))
static if(__traits(isSame, extension, KHR_portability_subset))
enum VK_KHR_PORTABILITY_SUBSET_SPEC_VERSION = 1;

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