See #165 . It was possible before with some js.InternalObject hack, but I did not like the solution and wanted to provide an officially supported one.

@dominikh asked me to explain ArrayBufferView vs ArrayBuffer some more:

The ArrayBuffer is like a Go byte array of some fixed size. The ArrayBufferView is an abstract type, the concrete versions are Uint8Array, Int32Array, etc. Each ArrayBufferView is backed by an ArrayBuffer, just like a Go byte slice is backed by a byte array. Each ArrayBufferView has an offset and a length, also just like a Go slice. However, this offset and length and the read/write methods of an ArrayBufferView depend on the concrete type when finding the correct byte position in the underlying ArrayBuffer.

Hope this helps a bit.