gistfile1.txt

class Box(boxtype, extended_type)
{
	uint(32) size;
	string(4) type;
	@args.boxtype = type;
	if(size == 1)
	{
		uint(64) largesize;
		@size = 8*largesize;
	}
	else
	{
		@size = 8*size;
	}
	if(type == "uuid")
	{
		uuid usertype;
		@args.extended_type = usertype;
	}
}

class NextFragPtsBox as Box("uuid", "D4807EFF2-CA39-4695-8E5426CB9E46A79F")
{
    uint(8) data[5];
    int(64) next_frag_pts;
}