MODULE lili;

(*     Linked Lists with Mocka		*)

IMPORT InOut, Strings, SYSTEM;

FROM   MemPools		IMPORT	KillPool, MemPool, NewPool, PoolAllocate;


TYPE   Identifier        = ARRAY [0..57] OF CHAR;
       NamePtr	    	 = POINTER TO NameNode;
       NameNode		 = RECORD
       			      Name	: Identifier;
			      next	: NamePtr
       			   END;

VAR    string		 : Identifier;
       allNames	 	 : MemPool;
       FirstName	 : NamePtr;


PROCEDURE StoreName (str   : Identifier) : BOOLEAN;

VAR	  this, prev, new	   : NamePtr;
	  result   	   	   : INTEGER;

BEGIN
   this := FirstName;
   prev := NIL;
   LOOP
      result := Strings.compare (this^.Name, str);
      IF  result = 0  THEN  RETURN FALSE  END;
      IF  result = 1  THEN  EXIT  END;
      prev := this;
      this := this^.next
   END;
   PoolAllocate (allNames, new, SYSTEM.TSIZE (NameNode));
   new^.Name := str;
   new^.next := this;
   IF  prev = NIL  THEN
      FirstName := new
   ELSE
      prev^.next := new
   END;
   RETURN TRUE
END StoreName;


PROCEDURE PrintNames;

VAR	  ThisOne    		: NamePtr;

BEGIN
   ThisOne := FirstName;
   IF  Strings.StrEq (ThisOne^.Name, "Guard")  THEN  ThisOne := ThisOne^.next  END;
   LOOP
      InOut.WriteString (ThisOne^.Name);		InOut.WriteLn;
      IF  ThisOne^.next = NIL  THEN
         EXIT
      ELSE
         ThisOne := ThisOne^.next
      END
   END
END PrintNames;


PROCEDURE Init;

BEGIN
   NewPool (allNames);
   PoolAllocate (allNames, FirstName, SYSTEM.TSIZE (NameNode));
   WITH  FirstName^  DO
      Name := "|";
      next := NIL
   END
END Init;


BEGIN
   Init;
   LOOP
      InOut.ReadString (string);
      IF  Strings.StrEq (string, "Exit")  THEN  EXIT  END;
      IF  StoreName (string) = FALSE  THEN
         InOut.WriteString (">>> Duplicate name");
	 InOut.WriteLn
      END
   END;
   PrintNames;
   KillPool (allNames)
END lili.