function unstack_(x, axis = 0) {
    const $x = (0, _tensorUtilEnv.convertToTensor)(x, "x", "unstack", "string_or_numeric");
    _util.assert(axis >= -$x.shape.length && axis < $x.shape.length, ()=>`Axis = ${axis} is not in [-${$x.shape.length}, ${$x.shape.length})`);
    const inputs = {
        value: $x
    };
    const attrs = {
        axis
    };
    return (0, _engine.ENGINE).runKernel((0, _kernelNames.Unpack), inputs, attrs);
}
Unstacks a `tf.Tensor` of rank-`R` into a list of rank-`(R-1)` `tf.Tensor`s.

```js
const a = tf.tensor2d([1, 2, 3, 4], [2, 2]);

tf.unstack(a).forEach(tensor => tensor.print());
```

@param x A tensor object.
@param axis The axis to unstack along. Defaults to 0 (the first dim).

@doc {heading: 'Tensors', subheading: 'Slicing and Joining'}