MODULE; IMPORT Rd, Stdio, TextRefTbl, Thread, Wr; PROCEDURE Main DoIt () = <*FATAL Rd.Failure, Rd.EndOfFile, Wr.Failure, Thread.Alerted *> VAR txt: TEXT; seen := NEW (TextRefTbl.Default).init (200); BEGIN WHILE NOT Rd.EOF (Stdio.stdin) DO txt := Rd.GetLine (Stdio.stdin); IF NOT seen.put (txt, NIL) THEN Wr.PutText (Stdio.stdout, txt); Wr.PutText (Stdio.stdout, Wr.EOL); END; END; END DoIt; BEGIN DoIt (); END Main.