IMPORTS

Of course, it might simply be a case of bad design :-)

But if you must reference like that, why not create a base type that they both extend...
eg:

flyingobjectthingy.bmx :

Type TFlyingObjectThingy
  Field x, y

  Method IAmHit(byMissile:TFlyingObjectThingy)
  End Method
End Type


ship.bmx :

import "flyingobjectthingy.bmx"
import "missile.bmx"

Type TShip extends TFlyingObjectThingy
  Field aMissile:TMissile

  Method IAmHit(byMissile:TFlyingObjectThingy)
    Local theMissile:TMissile = TMissile(byMissile)
    Print "Ouch"
  End Method

  Method fireAMissile()
    aMissile = new TMissile
    ....
  End Method
End Type


missile.bmx :

import "flyingobjectthingy.bmx"

Type TMissile extends TFlyingObjectThingy
  ...
  Method HitShip()
    Local theHitShip:TFlyingObjectThingy = someCollisionMethod()

    theHitShip.IAmHit( Self )
  End Method
End Type

The missile doesn't *have* to know what a ship is...

However, Max is a wee bit limited in that it only supports Extend and not Interfaces too, but it's workable...

At the end of the day, sue whatever way works for you...

:o)