How does the author use foreshadowing in Le Cid?

There is an ironic piece of foreshadowing in the Infanta's comments that the man who conquers Gomez will be able to conquer kingdoms. This foreshadows the final moments of the play in which Roderick conquers Gomez and receives orders from the King to conquer a kingdom. The irony, of course, is that the idea originates in the Infanta's fantasy, her love-struck hope that she and Roderick can have a life together. She believes it's impossible, and then when her fantasy actually comes true, it's too late because by then, Roderick and Chimene have agreed to marry.