MODULE expand; (* DEE 2014-08-06/2015-12-02/2022-09-23 *)
  (* Software Tools in Pascal, exercise 2-9. *)
  FROM ST IMPORT getc, putc;
  FROM STchars IMPORT ENDFILE, character;
  FROM STutility IMPORT isupper;
  FROM CE IMPORT FIRSTREP, WARNING;

  (* Uncompress standard input, (see compress). *)
  PROCEDURE expand;
    VAR
      c: character;
      n: INTEGER;
  BEGIN
    WHILE (getc(c) # ENDFILE) DO
      IF (c # WARNING) THEN
        putc(c)
      ELSIF (isupper(getc(c))) THEN
        n := c - FIRSTREP + 1;
        IF (getc(c) # ENDFILE) THEN
          FOR n := n TO 1 BY -1 DO
            putc(c)
          END
        ELSE putc(WARNING);
          putc(n - 1 + FIRSTREP)
        END
      ELSE putc(WARNING);
        IF (c # ENDFILE) THEN
          putc(c)
        END
      END
    END
  END expand;

BEGIN
  expand
END expand.