Unicode supplemental planes in Harbour

[KevinC]

Surely Przemek and Viktor and everyone helping them know that

• Unicode is more than a 16 bit encoding
• its upper limit is 0x10FFFF, not 0xFFFF
• it consists of 17 "planes", each of which contains 2^16 characters
• the first plane, the Basic Multilingual Plane (BMP), has code points 0 to 0xFFFF
• the other 16 planes, the supplemental planes, have code points 0x10000 to 0x10FFFF
• the first supplemental plane, the Supplemental Multilingual Plane (SMP), has code points 0x10000 to 0x1FFFF
  
• until recently only the BMP was normally used
• the recent addition of emoticons like 😊 😲😔 to the SMP has made it much more popular
  

Why then do we see the following?

• UTF8 for U+F60A <private-use-F60A> = e"\xEF\x98\x8A"
• UTF8 for U+1F60A SMILING FACE WITH SMILING EYES = e"\xF0\x9F\x98\x8A"
• HB_UTF8CHR(0x1F60A) --> e"\xEF\x98\x8A"
• HB_NUMTOHEX(HB_UTF8ASC(HB_UTF8CHR(0x1F60A))) --> "F60A"
• HB_NUMTOHEX(HB_UTF8ASC(e"\xF0\x9F\x98\x8A")) --> "F60A"

Is it a bug or a feature?

[KevinC]

A few years ago, I wrote a small library called UnicodeLib, written in pure Harbour, that has conversion functions written that handle all Unicode planes - http://kevincarmody.com/software/unicodelib.zip