How does the author use foreshadowing in Streamers?

In the opening scene, Martin (his only appearance) has just slit one of his wrists because he does not want to be in the Army any more. Richie takes him to the infirmary and that is the last the audience sees of him. His function in the play is to demonstrate Richie's nurturing, feminine nature, as well as to foreshadow the knife fight at the end of the play. Martin's suicide attempt illustrates from the beginning that conflict leads to violence.