| Value | Meaning |
|---|---|
| NOT_REORDERED0 | Spacing and enclosing marks; also many vowel and consonant signs, even if nonspacing |
| OVERLAY1 | Marks which overlay a base letter or symbol |
| NUKTA7 | Diacritic nukta marks in Brahmi-derived scripts |
| KANA_VOICING8 | Hiragana/Katakana voicing marks |
| VIRAMA9 | Viramas |
| CCC1010 | |
| CCC1111 | |
| CCC1212 | |
| CCC1313 | |
| CCC1414 | |
| CCC1515 | |
| CCC1616 | |
| CCC1717 | |
| CCC1818 | |
| CCC1919 | |
| CCC2020 | |
| CCC2121 | |
| CCC2222 | |
| CCC2323 | |
| CCC2424 | |
| CCC2525 | |
| CCC2626 | |
| CCC2727 | |
| CCC2828 | |
| CCC2929 | |
| CCC3030 | |
| CCC3131 | |
| CCC3232 | |
| CCC3333 | |
| CCC3434 | |
| CCC3535 | |
| CCC3636 | |
| CCC8484 | |
| CCC9191 | |
| CCC103103 | |
| CCC107107 | |
| CCC118118 | |
| CCC122122 | |
| CCC129129 | |
| CCC130130 | |
| CCC133132 | |
| ATTACHED_BELOW_LEFT200 | Marks attached at the bottom left |
| ATTACHED_BELOW202 | Marks attached directly below |
| ATTACHED_ABOVE214 | Marks attached directly above |
| ATTACHED_ABOVE_RIGHT216 | Marks attached at the top right |
| BELOW_LEFT218 | Distinct marks at the bottom left |
| BELOW220 | Distinct marks directly below |
| BELOW_RIGHT222 | Distinct marks at the bottom right |
| LEFT224 | Distinct marks to the left |
| RIGHT226 | Distinct marks to the right |
| ABOVE_LEFT228 | Distinct marks at the top left |
| ABOVE230 | Distinct marks directly above |
| ABOVE_RIGHT232 | Distinct marks at the top right |
| DOUBLE_BELOW233 | Distinct marks subtending two bases |
| DOUBLE_ABOVE234 | Distinct marks extending above two bases |
| IOTA_SUBSCRIPT240 | Greek iota subscript only |
| INVALID255 | Invalid combining class |
Data type for the Canonical_Combining_Class (ccc) property from the Unicode Character Database.
<note>Note: newer versions of Unicode may add new values. Client programs should be ready to handle any value in the 0..254 range being returned from hb_unicode_combining_class().</note>