Manual: Type-Checked Assignments and Array Slicing example code doesn't work

Two of the example assignments in Type-Checked Assignments cause errors:

let b[str] = [two three]

ion: assignment error: multi-dimensional arrays are not yet supported

let d:float[] = [5.1 6.2 7.3]

ion: assignment error: invalid type supplied: float[]

Another two in Slicing Syntax:

echo @array[0,3..]

ion: expansion error: index 'Key(On stack: '0,3..')' is not valid for array variable 'array'

echo @array[30,-3..]

ion: expansion error: index 'Key(On stack: '30,-3..')' is not valid for array variable 'array'

I assume these are unimplemented features. Should they be removed from the manual until they work?