INTERFACE Convert;

This interface provides binary/ASCII conversions for INTEGERs, REALs and LONGREALs.

Index: conversion; numbers; ASCII

TYPE
  Buffer = ARRAY OF CHAR;
  Base   = [2..16];

TYPE
  Style  = {Flo, AltFlo, Sci, AltSci, Mix};
  (* formatting styles for REALs:
         Flo:       xxx.yyy
         AltFlo:    xxx.yyy             (trailing zeros are suppressed)
         Sci:       xxx.yyy'E'exponent  ('D' for LONGREAL)
         AltSci:    xxx.yyy'E'exponent  (trailing zeros are suppressed)
         Mix:       == AltFlo unles AltSci is shorter;  if AltFlow is
                       selected and there are no zeros after the decimal
                       point, the decimal point is suppressed.
  *)

EXCEPTION Failed;

The From procedures convert binary values to ASCII character strings. Each procedure returns the number of characters that resulted. Extra space in the buffers is left unmodified. Failed is raised if the supplied buffer is too small to hold the result.

PROCEDURE FromInt (
    VAR buf    : Buffer;
        value  : INTEGER;
        base   : Base := 10;
        prefix : BOOLEAN := FALSE): INTEGER
  RAISES {Failed};

converts value to ASCII in the specified base and stores the result in buf. If prefix=TRUE, include the base prefix in the result.

PROCEDURE FromLongInt (
    VAR buf    : Buffer;
        value  : LONGINT;
        base   : Base := 10;
        prefix : BOOLEAN := FALSE): INTEGER
  RAISES {Failed};

converts value to ASCII in the specified base and stores the result in buf. If prefix=TRUE, include the base prefix in the result.

PROCEDURE FromUnsigned (
    VAR buf    : Buffer;
        value  : INTEGER;
        base   : Base := 10;
        prefix : BOOLEAN := FALSE): INTEGER
  RAISES{Failed};

treats value as unsigned, converts it to ASCII in the specified base and stores the result in buf. If prefix=TRUE, include the base prefix in the result.

PROCEDURE FromLongUnsigned (
    VAR buf    : Buffer;
        value  : LONGINT;
        base   : Base := 10;
        prefix : BOOLEAN := FALSE): INTEGER
  RAISES{Failed};

treats value as unsigned, converts it to ASCII in the specified base and stores the result in buf. If prefix=TRUE, include the base prefix in the result.

PROCEDURE FromFloat (
    VAR buf       : Buffer;
        value     : REAL;
        precision : INTEGER := 6;
        style     := Style.Mix): INTEGER
  RAISES {Failed};

converts value to ASCII in the given style and stores the result in buf. The precision is the number of fractional digits.

PROCEDURE FromLongFloat (
    VAR buf       : Buffer;
        value     : LONGREAL;
        precision : INTEGER := 6;
        style     := Style.Mix): INTEGER
  RAISES {Failed};

converts value to ASCII in the given style and stores the result in buf. The precision is the number of fractional digits.

PROCEDURE FromExtended (
    VAR buf       : Buffer;
        value     : EXTENDED;
        precision : INTEGER := 6;
        style     := Style.Mix): INTEGER
  RAISES {Failed};

converts value to ASCII in the given style and stores the result in buf. The precision is the number of fractional digits.

The To procedures convert ASCII character strings to their corresponding binary representations. The procedures convert the maximum number of characters possible. The number of characters actually used is returned in 'used'.

PROCEDURE ToInt (
    READONLY buf  : Buffer;
         VAR used : INTEGER;
             base : Base := 10): INTEGER
  RAISES {};

converts an integer. The characters are interpreted in the specified base unless an explicit base prefix is in the number.

PROCEDURE ToLongInt (
    READONLY buf  : Buffer;
         VAR used : INTEGER;
             base : Base := 10): LONGINT
  RAISES {};

converts an integer. The characters are interpreted in the specified base unless an explicit base prefix is in the number.

PROCEDURE ToUnsigned (
    READONLY buf  : Buffer;
         VAR used : INTEGER;
             base : Base := 10): INTEGER
  RAISES {};

converts an unsigned number. The characters are interpreted in the specified base unless an explicit base prefix is in the number.

PROCEDURE ToLongUnsigned (
    READONLY buf  : Buffer;
         VAR used : INTEGER;
             base : Base := 10): LONGINT
  RAISES {};

converts an unsigned number. The characters are interpreted in the specified base unless an explicit base prefix is in the number.

PROCEDURE ToFloat (
    READONLY buf  : Buffer;
         VAR used : INTEGER): REAL
  RAISES {Failed};

converts a floating point number.

PROCEDURE ToLongFloat (
    READONLY buf  : Buffer;
         VAR used : INTEGER): LONGREAL
  RAISES {Failed};

converts a floating point number.

PROCEDURE ToExtended (
    READONLY buf  : Buffer;
         VAR used : INTEGER): EXTENDED
  RAISES {Failed};

converts a floating point number.

END Convert.