ISO/IEC JTC1/SC2/WG2 N2647
2003-10-13
Universal Multiple-Octet Coded Character Set
International Organization for Standardization
Organisation Internationale de NormalisationМеждународная организация по стандартизацииDoc Type: Working Group Document
Title:
Further discussion of the DOUBLE OBLIQUE HYPHEN
Source: Michael Everson
Status:Individual Contribution
Action:For consideration by JTC1/SC2/WG2 and UTC
Date:
2003-10-13
Continued e-mail discussion of the character DOUBLE OBLIQUE HYPHEN proposed in N2611, N2636, andN2639 has resulted in the present document. It has been urged that a document be produced which willaddress certain implementation concerns.
Semiticists and Cuneiformists familiar with German scholarship were aware that the glyph for U+002D
HYPHEN-MINUS which is used in Fraktur typography differs from the glyph used in Roman typography.
They have made use of this glyph to indicate certain morphological boundaries while continuing to use
the ordinary hyphen to indicate other boundaries. Certainly they were distinguishing between the twocharacters. Research has shown that they also make use of the ordinary U+003D EQUALS SIGN in othercontexts in their documents.
It is interesting to note that other linguists have made use of U+003D EQUALS SIGN to indicate the samekind of morphological boundary. It was suggested that the U+003D EQUALS SIGN be pressed into service
with a non-plain text glyph variant in order to represent the Fraktur borrowing, but this is not satisfactory.
The EQUALS SIGN has at least variant already (the longer version used in some mathematical typography),and the suggestion that it has adopted an alternate “Copto-Hittite” variant seems to many to be amisunderstanding of the underlying character identity, in addition to introducing a glyph variant for thatcharacter which would not be acceptable to anyone in a mathematical context. I suggest that it is theadvent of computers which had equals signs and the abandonment of lead typefaces which had Fraktur
double oblique hyphens in them might have something to do with conflation of the two characters.
Accordingly it is proposed to add a new character: U+xxxx DOUBLE OBLIQUE HYPHEN. This character is
not intended to be used for any instance of an EQUALS SIGN which would be rendered =, even if thelinguistic context might otherwise be similar or identical (in other words, there is a glyph-based
distinction for what might otherwise be the same semantic function – comparable to the way modifier
letters are treated). This character is also not intended to be used for instances of a Fraktur style hyphen,which should be encoded with U+002D, instead.
The repertoire of relevant glyphs is as follows:
AB
CDE
FG

›
–=
›–
=

short, single-bar
short, double-bar, uptilted
medium, single-bar
medium, double-bar
medium, double-bar, uptilted
medium+, single-bar (shorter than em dash)medium+, double-bar
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The repertoire of relevant characters is as follows:
123
4
5
6U+002D
U+2010U+2013
U+2212
U+003D
U+xxxxHYPHEN-MINUS
HYPHENEN DASH
MINUS SIGNEQUALS SIGNDOUBLE OBLIQUE HYPHEN

Rendering rules:
1. U+002D HYPHEN-MINUS is ambiguous between use as a hyphen (A: - ) and use as a minus sign (C: – ),and may be rendered as either of those, depending on use and context.
2. U+2010 HYPHEN is normally rendered with glyph A ( - ). In Fraktur style it is rendered with glyph B( › ). In some fallback contexts it is rendered with glyph C ( – ).
3. U+2013 EN DASH is a fixed width dash, and should normally be rendered with glyph C ( – ). In some
European typographic styles which emphasize the length of dashes as opposed to hyphens, it may end
up rendered with glyph F ( – ) – but still shorter than an emdash or quotation dash.
4. U+2212 MINUS SIGN is normally rendered with glyph C ( – ). In fonts which exaggerate mathematicaloperator size, it may be rendered with glyph F ( – ).
5. U+003D E Q U A L S S I G N is normally rendered with glyph D ( = ). In fonts which exaggeratemathematical operator size, it may be rendered with glyph G ( = ), and in any case should normally
have the same width as the minus sign.
6. U+xxxx DOUBLE OBLIQUE HYPHEN is normally rendered with glyph B ( › ). In certain typographiccontexts (e.g. the French Coptic grammar), it may be rendered with glyph E ( › ) – but this is rather
old-fashioned..

Unicode Character Properties
2055;DOUBLE OBLIQUE HYPHEN;Pd;0;ON;;;;;N;;;;;

Bibliography
Fossey, Charles. 1948. Notices sur les caractères étrangers anciens et modernes rédigées par un groupe esavants. Nouvelle édition míse à jour à l’occasion du 21e Congrès des Orientalistes. Paris: Imprimerie
Nationale de France.
Güterbock, Hans G. & Harry A. Hoffner, eds. 1994. The Hittite dictionary of the Oriental Insitute of theUniversity of Chicago. Chicago: Oriental Insitute of the University of Chicago.
Haarmann, Harald. 1990. Die Universalgeschichte der Schrift. Frankfurt: Campus Verlag. ISBN 3-59334346-0
Plumley, J. Martin. 1948. An introductory Coptic grammar (Sahidic dialect). London: Home & van Thal.
Seidel, A. [s.d]. Praktische Grammatiken der Hauptsprachen Deutsch-Südwestafrikas. I. Nama (Spracheder Nama-Hottentotten). II. Otyiherero (Sprache der Herero). III. Oshindonga (Sprache des NdongaStammes der Ovambo). Wien und Leipzig: A. Hertleben’s Verlag.
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Starke, Frank. 1977. Die Funktionen der dimensionalen Kasus und Adverbien im Althethitischen.
(Studien zu den Boğazköy-Texten; 23) Wiesbaden: Otto Harrassowitz.
Till, Walter C. 1966. Koptische Grammatik: saïdischer Dialekt, mit Bibliographie, Lesestücken undWörterverzeichnissen. Leipzig: VEB Verlag Enzykopädie.

ExamplesFigure 1. In this example from Seidel the HYPHEN is used in both the Fraktur font (›) and the Roman font(-). Here it is clear that the same character (U+002D) is being used with only a font distinction. It is also
used as a connector in Khoi-Khoin and in Cape-Town.

Figure 2. In this example from Seidel the HYPHEN is used at a linebreak in Wörterbuch. Both the HYPHEN(drawn in Fraktur as a double hyphen) and a short horizontal dash with extra space on either side are usedin Deut¬ › Otyiherero – Ohikuanjama. Today, in English, we encode such a distinction in Roman as
Deutsch–Otyiherero-Oshikuanjama, where the EN DASH serves to separate the first element from theHYPHENated compound second element; this use of EN DASH is not known in modern German.

Figure 3. In this example from Seidel the HYPHEN (drawn in Fraktur as a double hyphen) is uses in wordbreaking, and is also used (drawn in Roman as a single hyphen) to show morphological boundaries. TheEM DASH is used to link translations, and the EQUALS SIGN is used to show equivalence.
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F i g u re 4. Sample text from Ti l l ’s grammar showing the use of the D O U B L E O B L I Q U E H Y P H E N ,distinguished from the ordinary single hyphen.

Figure 5. Text from Fossey 1948 describing the use of the horizontal stroke over numerals and thedouble horizontal stroke over thousands. The text also describes the use of the acute accent to indicate
tonic accent, and the distinction between HYPHEN (trait d’union ‘stroke of union’) and DOUBLE OBLIQUE
HYPHEN (deux traits obliques ‘two oblique strokes’).

Figure 6. The DOUBLE OBLIQUE HYPHEN with its use described in the Webster's Third New International
Dictionary.
4F i g u re 7. Example in Roman type from Güterbock & Hoffman 1994 showing the DOUBLE OBLIQUE
HYPHEN distinguished from the HYPHEN as well as from the EQUALS SIGN.

F i g u re 8. Example from Starke 1977 showing the DOUBLE OBLIQUE HYPHEN distinguished from theHYPHEN as well as from the EQUALS SIGN.

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Figure 9. Plumley 1948 describes the use of the HYPHEN and the DOUBLE OBLIQUE HYPHEN.

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