DEFINITION MODULE Conversions;
(* Scalar <-> string conversions.  Output strings are NUL-terminated.
   The StrTo* procedures report an ISO-style `ConvResults` status:
     strAllRight    the whole string was a valid literal
     strOutOfRange  valid literal but not representable in the target
     strWrongFormat the string is not a literal of the target type
     strEmpty       the string was empty
   The BOOLEAN-returning wrappers are retained for convenience. *)

TYPE ConvResults = (strAllRight, strOutOfRange, strWrongFormat, strEmpty);

PROCEDURE IntToStr(n : INTEGER; VAR s : ARRAY OF CHAR);
PROCEDURE CardToStr(n : CARDINAL; VAR s : ARRAY OF CHAR);
PROCEDURE RealToStr(x : REAL; VAR s : ARRAY OF CHAR);

PROCEDURE StrToInt(s : ARRAY OF CHAR; VAR n : INTEGER) : ConvResults;
PROCEDURE StrToCard(s : ARRAY OF CHAR; VAR n : CARDINAL) : ConvResults;
PROCEDURE StrToReal(VAR s : ARRAY OF CHAR; VAR x : REAL) : ConvResults;

(* BOOLEAN shortcuts: TRUE iff the status is strAllRight. *)
PROCEDURE IntVal(s : ARRAY OF CHAR; VAR n : INTEGER) : BOOLEAN;
PROCEDURE CardVal(s : ARRAY OF CHAR; VAR n : CARDINAL) : BOOLEAN;
PROCEDURE RealVal(VAR s : ARRAY OF CHAR; VAR x : REAL) : BOOLEAN;

END Conversions.