Let's assume the array is in slot 1 and is named ARRAY, and it's 1D.
We use the functional VAR() keyword to grab a reference to the variable, using its name string.
PRINT VAR("1:ARRAY")[0]
Note that the index brackets come after the VAR function. Assignment works like this too:
VAR("1:ARRAY")[0]=10
Keep in mind that this may not work as intended depending on the way everything is set up.