Unicode
When the double hyphen is used as a functionally equivalent graphical variant of the single hyphen, it is represented in Unicode as a normal hyphen.
When used as a punctuation mark distinct from the single hyphen, the double hyphen is represented in Unicode by two different code points. A third code point has been assigned for the use of a generic (non-Asian) double hyphen at U+2E40, though this character is still under ballot and has not been formally adopted in the standard.
| Name | Glyph | Code point | Purpose |
|---|---|---|---|
| DOUBLE OBLIQUE HYPHEN | ⸗ | U+2E17 | Western orthography (including Coptic language scholarship) |
| DOUBLE HYPHEN | ⹀ | U+2E40 (under ballot) | (in Latin and other scripts) |
| KATAKANA-HIRAGANA DOUBLE HYPHEN | ゠ | U+30A0 | Japanese and Ainu orthography (in Kana or Kanji script) |
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