Scalactic Or in for compresension with 'if' guard

[Joost den Boer]

I'm trying to use an Or in a for-compresension with an 'if' guard, but this gives me a

`type mismatch; found: Boolean, required: org.scalactic.Validation[?]` compile error.

code example

```

type Result = String or Int

def someFunctionWithResult: Result

for {

  or <- someFunctionWithResult

  if (or == "ok?")

} yield or

```

Am I doing it wrong or is it just because the 'Or' only has a 'filter' method which takes a 'Validation' instance.

I already have a 'predicateAsValidation' function, but this is not usable in the for-comprehension context.

```

def predicateAsValidation[A](predicate: A => Boolean)(a: A): Validation[One[ErrorMessage]] =
  if (predicate(a)) Pass else Fail(One(FilterMismatchError(a.toString)))

```