MODULE Showcase17;
// Session showcase: Clarion CLASS lowering, CHAR-array string
// concatenation, and ISO ConvResults.
//
// A Bounded counter class (single inheritance from Counter) is driven
// through its hidden THIS receiver; a value is parsed with the
// ConvResults API, and a label is built by CHAR-array concatenation
// for the output line.
// Expected ExitCode: 42.
IMPORT TextIO, Conversions;
FROM Conversions IMPORT strAllRight, strWrongFormat, strOutOfRange;

TYPE
  CLASS Counter;
    total : INTEGER;
    PROCEDURE Bump(by : INTEGER);
    PROCEDURE Value() : INTEGER;
  END Counter;

  CLASS Bounded (Counter);        (* single inheritance *)
    limit : INTEGER;
    PROCEDURE SetLimit(v : INTEGER);
    PROCEDURE Over() : BOOLEAN;
  END Bounded;

CLASS IMPLEMENTATION Counter;
  PROCEDURE Bump(by : INTEGER);
  BEGIN total := total + by END Bump;
  PROCEDURE Value() : INTEGER;
  BEGIN RETURN total END Value;
END Counter;

CLASS IMPLEMENTATION Bounded;
  PROCEDURE SetLimit(v : INTEGER);
  BEGIN limit := v END SetLimit;
  PROCEDURE Over() : BOOLEAN;
  BEGIN RETURN total > limit END Over;
END Bounded;

VAR ExitCode : INTEGER;
VAR c : Bounded;
VAR n : INTEGER;
VAR label : ARRAY [0 .. 31] OF CHAR;
VAR msg : ARRAY [0 .. 63] OF CHAR;
VAR r : Conversions.ConvResults;

BEGIN
  ExitCode := 0;

  (* class methods: own + inherited, through the receiver *)
  c.SetLimit(100);
  c.Bump(15);
  c.Bump(27);                       (* total = 42 *)
  IF c.Value() = 42 THEN ExitCode := ExitCode + 1 ELSE ExitCode := 100 END;
  IF NOT c.Over() THEN ExitCode := ExitCode + 2 ELSE ExitCode := 100 END;

  (* ISO ConvResults *)
  r := Conversions.StrToInt("-42", n);
  IF (r = strAllRight) AND (n = -42) THEN
    ExitCode := ExitCode + 4
  ELSE ExitCode := 100 END;
  r := Conversions.StrToInt("nope", n);
  IF r = strWrongFormat THEN ExitCode := ExitCode + 8 ELSE ExitCode := 100 END;
  r := Conversions.StrToInt("99999999999", n);
  IF r = strOutOfRange THEN ExitCode := ExitCode + 16 ELSE ExitCode := 100 END;

  (* CHAR-array concatenation *)
  Conversions.IntToStr(c.Value(), label);
  msg := "showcase17 total=" + label;
  TextIO.WriteString(msg);
  TextIO.WriteLn;

  IF ExitCode = 31 THEN ExitCode := c.Value() END   (* 42 *)
END Showcase17.