how to use multiple modofier to form combinations of boolean conditions?

Question

I have read this article and this SO. And I understand the functionality of modifier. When modifiers are placed on a function with a spacing they will be evaluated in the order of placing thus creating an And condition. However, I would to understand how multiple modifiers can be placed so that combination of other Boolean conditions such as OR be evaluated?

For Instance,

modifier modA {
  // verify something
  _;
  // verify something
  _;
}
modifier modB {
  // verify something
  _;
  // verify something
  _;
}
function Fun() modA modB {
  // Do something
}

In this case, modA AND modB will be the execution. But is it possible to use them to form OR condition?

Answer 1

There is no direct way in solidity. I'll explain you why. Modifier is like a macro function while compiling it will replace your modifier with its actuval implementation. Here _; replace with your function implementation.

contract ModiferTesting {
   uint public a;
   uint public b;
   uint public c;

   modifier modA() {
    a = a + 1;
    _;
   }

   modifier modB() {
    b = b + 1;
    _;
    b = b + 1;
    _;
    b = b + 1;
    _;
  }

  function test() public modA modB {
    c = c + 1;
  }
}

If you debug, above code you can find a=1, b=3, c=3

Try to write an other modifier that check's or condition.