Version Information

• vyper Version (output of vyper --version): 0.3.8+commit.046ea166
• OS: OSX
• Python Version (output of python --version): 3.8.0

What's your issue about?

Range expressions, when formed as range(x, x + CONSTANT), prevent x to be a call to state modifying functions. For example, the following contract would compile only if bar was a view or a pure function. Under its current form, the compiler raise a StateAccessViolation with the following reason: May not call state modifying function 'bar' within a range.

@internal
def bar()->uint256:
    return 0

@external
def test()-> (DynArray[uint256,6]):
    b:DynArray[uint256,6] = []
    for i in range(self.bar(),self.bar()+2):
        b.append(i)
    return b

However, it is possible to call the DynArray's pop function inside the range expression. If the dynamic array from which a value is popped is a state variable, the range expression is effectively calling a state modifying function. Note that only one value is popped.
For example, this contract compiles and a call to test output ([0,1],[1]), meaning that arr has been modified by the range by popping one value.

arr:DynArray[uint256,10]
@external
def test()-> (DynArray[uint256,6],DynArray[uint256,10]):
    b:DynArray[uint256,6] = []
    self.arr = [1,0]
    for i in range(self.arr.pop(),self.arr.pop()+2):
        b.append(i)
    return b,self.arr # return ([0, 1], [1])