Platform_Extensions.VK_KHR_XLIB_SURFACE_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))
enum VK_KHR_XLIB_SURFACE_SPEC_VERSION = 6;

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