Hello. I would like to have a "source failure indicator symbol" (SFIS) charakter in the unicode, which a charset-convertion unit may insert into a text (Suggeested position: U+FFF8).
Reason: several charsets have undefined codepoints which were defined in a former or later version (eg. overlong UTF-8 encodings or the $ symbol (0x24) in the INVARIANT charset). A converter can replace such symbols by U+FFFD (which is correct but loses the information), or simply use the charakter which most likely is intended (which hides the error). Both is not very good. The SFIS would allow the reader to see that an error occured and therefore the following charakter may be incorrect, but maintain the readability if the right conversion is made anyway (or at least give a hint which charakter may be intended - eg. the $ sign could have been any other currency symbol if a national 7-bit charset was changed to INVARIANT by previous conversions). Of course a converter can still use U+FFFD if it has no idea which character is intended or if unicode doesn't contain the character. The whole "charakter identities"-discussion gave me another reason to introduce such a SFIS-charakter: A font-renderer may show the SFIS before a charakter which is replaced by another one because the correct one is not contained in the font (eg. it may render an "a with superscript e above" by SFIS + "a umlaut" to indcate the error and show an probably fitting replacement, which is much better than to show an empty square). In short words: The SFIS may indicate a kind of compatibility-decomposition of the following charakter. (this is not nessessarily the standard compatibility-decomposition). I'd like to hear if my suggestion is completely weird or if anybody else think it might be useful. Best Regards. -- Dominikus Scherkl [EMAIL PROTECTED]
