Fixed-size array issue

Question

Maybe this question it seems to be stupid but is it possible to change elements of fixed-size array like bytes32. For example:

bytes32 _b32 = sha3(1);
_b32[0] = 100; // => Error

Answer 1

It's possible to mutate elements of a fixed-sized array, but not a fixed-sized byte array (like bytes32).

So this is valid:

byte[32] myBytes;
myBytes[3] = 0x5;

but this is not valid:

bytes32 myBytes;
myBytes[3] = 0x5;  // TypeError: Expression has to be an lvalue.