Pattern matching is your friend :smile: 
```scala
for ((op1, op2) <- operations) {
  if (op1.source eq t1) {
    assert(op2.source eq t2
  } else {
    val (_, vs) = variables.find((v) => op1.source eq v._1).get
    assert(op2.source eq vs)
  }
}
```
Also, .get will crash if not found (but I think that's what you're expecting since you're doing assertions)