testWhere1 = a
where b = 1
a = b+1
> testWhere1
2
testWhere2 = a
where b = 1
c = 1/(b - b)
a = b+1
> testWhere2
2.0
The same thing happens with let.
testLet1 = let a = b+1
b = 1
in a
> testLet1
2
testLet2 = let a = b+1
c = 1/(b - b)
b = 1
in a
> testLet2
2.0