Re: Inquiring about the status of the proposed UNICODE library

[Alice Osako]

    Benjamin Kowarsch:

Basically you need two functions

PROCEDURE utf8ToUnichar ( utf8 : ARRAY [0..5] OF CARDINAL [0..127]; VAR ch : UNICHAR );

PROCEDURE unicharToUtf8 ( ch : UNICHAR; VAR utf8 : ARRAY [0..5] OF CARDINAL [0..127] );

I just noticed that I made a mistake in the above function signatures. For UTF-8, the I/O buffer elements should be of type CARDINAL [0..255] instead of CARDINAL [0..127]. The latter would be for UTF-7.

    Ah, that makes sense.

BTW, for portability, you should avoid using SHORTCARD. Define a type for CARDINAL [0..255]. This will be portable.

    Oh, excellent point, thank you.

You may also need a few utility functions such as:

PROCEDURE UCHR ( n : CARDINAL ) : UNICHAR;

(* Returns a UNICHAR value for code point n *)

PROCEDURE is7bitPrintable ( ch : UNICHAR ) : BOOLEAN;

(* Returns TRUE if ch represents a 7-bit printable character, else FALSE *)

PROCEDURE charFromUnichar ( ch : UNICHAR ) : CHAR;

(* Converts a UNICHAR value to type CHAR if ch is a 7-bit printable,

    causes a runtime error if ch does not represent a 7-bit printable *)

If you design the library for unqualified import, you may call the latter function toChar, calling it as Unichar.toChar().

    Ah, thank you very much, this helps tremendously.