Asserts the buffer was initialized with a capacity at least n.
pub fn takeVarInt(r: *Reader, comptime Int: type, endian: std.builtin.Endian, n: usize) Error!Int
pub fn takeVarInt(r: *Reader, comptime Int: type, endian: std.builtin.Endian, n: usize) Error!Int {
assert(n <= @sizeOf(Int));
return std.mem.readVarInt(Int, try r.take(n), endian);
}