.\"	$Id$
.\"
.\" Copyright (c) 2009 Kristaps Dzonsons <kristaps@kth.se>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\" 
.Dd $Mdocdate$
.Dt MANDOC_CHAR 7
.Os
.\" SECTION
.Sh NAME
.Nm mandoc_char
.Nd mandoc special characters
.\" SECTION
.Sh DESCRIPTION
This documents the special characters and predefined strings accepted by 
.Xr mandoc 1
to format
.Xr mdoc 7
and
.Xr man 7
documents.  Specific output devices of
.Xr mandoc 1 ,
dictated by the
.Fl T Ns Ar output
argument, will properly render these sequences.
.\" PARAGRAPH
.Pp
Both
.Xr mdoc 7
and
.Xr man 7
encode special characters with 
.Sq \eX
.Pq for a one-character escape ,
.Sq \e(XX
.Pq two-character ,
and
.Sq \e[N]
.Pq N-character .
One may generalise
.Sq \e(XX
as
.Sq \e[XX]
and
.Sq \eX
as
.Sq \e[X] .
Predefined strings are functionally similar to special characters, using 
.Sq \e*X
.Pq for a one-character escape ,
.Sq \e*(XX
.Pq two-character ,
and
.Sq \e*[N]
.Pq N-character .
One may generalise
.Sq \e*(XX
as
.Sq \e*[XX]
and
.Sq \e*X
as
.Sq \e*[X] .
.\" SECTION
.Sh Special Characters
These are the preferred input symbols for producing special characters.
.\" PARAGRAPH
.Pp
Typographic:
.Bl -tag -width Ds -offset indent -compact
.It \e~
.Pq non-breaking space
.It \e
.Pq space
.It \e^
.Pq zero-width space
.It \e%
.Pq zero-width space
.It \e&
.Pq zero-width space
.It \e|
.Pq zero-width space
.It \e0
.Pq white-space
.El
.\" PARAGRAPH
.Pp
Grammatic:
.Bl -offset indent -column 10n 10n 10n
.It \e(em      Ta \(em     Ta em-dash
.It \e(en      Ta \(en     Ta en-dash
.It \e(hy      Ta \(hy     Ta hyphen
.It \e\e       Ta \\       Ta back-slash
.It \\e        Ta \e       Ta back-slash
.It \e'        Ta \'       Ta apostrophe
.It \e`        Ta \`       Ta back-tick
.It \e.        Ta \.       Ta period
.It \e(r!      Ta \(r!     Ta upside-down exclamation
.It \e(r?      Ta \(r?     Ta upside-down question
.El
.\" PARAGRAPH
.Pp
Enclosures:
.Bl -offset indent -column 10n 10n 10n
.It \e(lh      Ta \(lh     Ta left hand
.It \e(rh      Ta \(rh     Ta right hand
.It \e(Fo      Ta \(Fo     Ta left guillemet
.It \e(Fc      Ta \(Fc     Ta right guillemet
.It \e(fo      Ta \(fo     Ta left guilsing
.It \e(fc      Ta \(fc     Ta right guilsing
.It \e(rC      Ta \(rC     Ta right brace
.It \e(lC      Ta \(lC     Ta left brace
.It \e(ra      Ta \(ra     Ta right angle
.It \e(la      Ta \(la     Ta left angle
.It \e(rB      Ta \(rB     Ta right bracket
.It \e(lB      Ta \(lB     Ta left bracket
.It \e(lq      Ta \(lq     Ta left double-quote
.It \e(rq      Ta \(rq     Ta right double-quote
.It \e(oq      Ta \(oq     Ta left single-quote
.It \e(aq      Ta \(aq     Ta right single-quote
.It \e(Bq      Ta \(Bq     Ta right low double-quote
.It \e(bq      Ta \(ba     Ta right low single-quote
.El
.\" PARAGRAPH
.Pp
Indicatives:
.Bl -offset indent -column 10n 10n 10n
.It \e(<-      Ta \(<-     Ta left arrow
.It \e(->      Ta \(->     Ta right arrow
.It \e(ua      Ta \(ua     Ta up arrow
.It \e(da      Ta \(da     Ta down arrow
.It \e(<>      Ta \(<>     Ta left-right arrow
.It \e(lA      Ta \(lA     Ta left double-arrow
.It \e(rA      Ta \(rA     Ta right double-arrow
.It \e(uA      Ta \(uA     Ta up double-arrow
.It \e(dA      Ta \(dA     Ta down double-arrow
.It \e(hA      Ta \(hA     Ta left-right double-arrow
.El
.\" PARAGRAPH
.Pp
Logical:
.Bl -offset indent -column 10n 10n 10n
.It \e(AN      Ta \(AN     Ta logical and
.It \e(OR      Ta \(OR     Ta logical or
.It \e(no      Ta \(no     Ta logical not
.It \e[tno]    Ta \[tno]   Ta logical not (text)
.It \e(te      Ta \(te     Ta existential quantifier
.It \e(fa      Ta \(fa     Ta universal quantifier
.It \e(st      Ta \(st     Ta such that
.It \e(tf      Ta \(tf     Ta therefore
.It \e(3d      Ta \(3d     Ta therefore
.It \e(or      Ta \(or     Ta bitwise or
.El
.\" PARAGRAPH
.Pp
Mathematical:
.Bl -offset indent -column 10n 10n 10n
.It \e(pl      Ta \(pl     Ta plus
.It \e(mi      Ta \(mi     Ta minus
.It \e-        Ta \-       Ta minus (text)
.It \e(-+      Ta \(-+     Ta minus-plus
.It \e(+-      Ta \(+-     Ta plus-minus
.It \e[t+-]    Ta \[t+-]   Ta plus-minus (text)
.It \e(pc      Ta \(pc     Ta centre-dot
.It \e(mu      Ta \(mu     Ta multiply
.It \e[tmu]    Ta \[tmu]   Ta multiply (text)
.It \e(c*      Ta \(c*     Ta circle-multiply
.It \e(c+      Ta \(c+     Ta circle-plus
.It \e(di      Ta \(di     Ta divide
.It \e[tdi]    Ta \[tdi]   Ta divide (text)
.It \e(f/      Ta \(f/     Ta fraction
.It \e(**      Ta \(**     Ta asterisk
.It \e(<=      Ta \(<=     Ta less-than-equal
.It \e(>=      Ta \(>=     Ta greater-than-equal
.It \e(<<      Ta \(<<     Ta much less
.It \e(>>      Ta \(>>     Ta much greater
.It \e(eq      Ta \(eq     Ta equal
.It \e(!=      Ta \(!=     Ta not equal
.It \e(==      Ta \(==     Ta equivalent
.It \e(ne      Ta \(ne     Ta not equivalent
.It \e(=~      Ta \(=~     Ta congruent
.It \e(-~      Ta \(-~     Ta asymptotically congruent
.It \e(ap      Ta \(ap     Ta asymptotically similar
.It \e(~~      Ta \(~~     Ta approximately similar
.It \e(~=      Ta \(~=     Ta approximately equal
.It \e(pt      Ta \(pt     Ta proportionate
.It \e(es      Ta \(es     Ta empty set
.It \e(mo      Ta \(mo     Ta element
.It \e(nm      Ta \(nm     Ta not element
.It \e(sb      Ta \(sb     Ta proper subset
.It \e(nb      Ta \(nb     Ta not subset
.It \e(sp      Ta \(sp     Ta proper superset
.It \e(nc      Ta \(nc     Ta not superset
.It \e(ib      Ta \(ib     Ta reflexive subset
.It \e(ip      Ta \(ip     Ta reflexive superset
.It \e(ca      Ta \(ca     Ta intersection
.It \e(cu      Ta \(cu     Ta union
.It \e(/_      Ta \(/_     Ta angle
.It \e(pp      Ta \(pp     Ta perpendicular
.It \e(is      Ta \(is     Ta integral
.It \e[integral] Ta \[integral] Ta integral
.It \e[sum]    Ta \[sum]   Ta summation
.It \e[product] Ta \[product] Ta product
.It \e[coproduct] Ta \[coproduct] Ta coproduct
.It \e(gr      Ta \(gr     Ta gradient
.It \e(sr      Ta \(sr     Ta square root
.It \e[sqrt]   Ta \[sqrt]  Ta square root
.It \e(lc      Ta \(lc     Ta left-ceiling
.It \e(rc      Ta \(rc     Ta right-ceiling
.It \e(lf      Ta \(lf     Ta left-floor
.It \e(rf      Ta \(rf     Ta right-floor
.It \e(if      Ta \(if     Ta infinity
.It \e(Ah      Ta \(Ah     Ta aleph
.It \e(Im      Ta \(Im     Ta imaginary
.It \e(Re      Ta \(Re     Ta real
.It \e(pd      Ta \(pd     Ta partial differential
.It \e(-h      Ta \(-h     Ta Planck constant over 2\(*p
.El
.\" PARAGRAPH
.Pp
Ligatures:
.Bl -offset indent -column 10n 10n 10n
.It \e(ss      Ta \(ss     Ta German eszett
.It \e(AE      Ta \(AE     Ta AE
.It \e(ae      Ta \(ae     Ta ae
.It \e(OE      Ta \(OE     Ta OE
.It \e(oe      Ta \(oe     Ta oe
.It \e(ff      Ta \(ff     Ta ff ligature
.It \e(fi      Ta \(fi     Ta fi ligature
.It \e(fl      Ta \(fl     Ta fl ligature
.It \e(Fi      Ta \(Fi     Ta ffi ligature
.It \e(Fl      Ta \(Fl     Ta ffl ligature
.El
.\" PARAGRAPH
.Pp
Accents:
.Bl -offset indent -column 10n 10n 10n
.It \e(a"      Ta \(a"     Ta Hungarian umlaut
.It \e(a-      Ta \(a-     Ta macron
.It \e(a.      Ta \(a.     Ta dotted
.It \e(a^      Ta \(a^     Ta circumflex
.It \e(aa      Ta \(aa     Ta acute
.It \e(ga      Ta \(ga     Ta grave
.It \e(ab      Ta \(ab     Ta breve
.It \e(ac      Ta \(ac     Ta cedilla
.It \e(ad      Ta \(ad     Ta dieresis
.It \e(ah      Ta \(ah     Ta caron
.It \e(ao      Ta \(ao     Ta ring
.It \e(a~      Ta \(a~     Ta tilde
.It \e(ho      Ta \(ho     Ta ogonek
.It \e(ha      Ta \(ha     Ta hat (text)
.It \e(ti      Ta \(ti     Ta tilde (text)
.El
.\" PARAGRAPH
.Pp
Accented characters:
.Bl -offset indent -column 10n 10n 10n
.It \e(-D      Ta \(-D     Ta Eth
.It \e(Sd      Ta \(Sd     Ta eth
.It \e(TP      Ta \(TP     Ta Thorn
.It \e(Tp      Ta \(Tp     Ta thorn
.It \e('A      Ta \('A     Ta acute A
.It \e('E      Ta \('E     Ta acute E
.It \e('I      Ta \('I     Ta acute I
.It \e('O      Ta \('O     Ta acute O
.It \e('U      Ta \('U     Ta acute U
.It \e('a      Ta \('a     Ta acute a
.It \e('e      Ta \('e     Ta acute e
.It \e('i      Ta \('i     Ta acute i
.It \e('o      Ta \('o     Ta acute o
.It \e('u      Ta \('u     Ta acute u
.It \e(`A      Ta \(`A     Ta grave A
.It \e(`E      Ta \(`E     Ta grave E
.It \e(`I      Ta \(`I     Ta grave I
.It \e(`O      Ta \(`O     Ta grave O
.It \e(`U      Ta \(`U     Ta grave U
.It \e(`a      Ta \(`a     Ta grave a
.It \e(`e      Ta \(`e     Ta grave e
.It \e(`i      Ta \(`i     Ta grave i
.It \e(`o      Ta \(`i     Ta grave o
.It \e(`u      Ta \(`u     Ta grave u
.It \e(~A      Ta \(~A     Ta tilde A
.It \e(~N      Ta \(~N     Ta tilde N
.It \e(~O      Ta \(~O     Ta tilde O
.It \e(~a      Ta \(~a     Ta tilde a
.It \e(~n      Ta \(~n     Ta tilde n
.It \e(~o      Ta \(~o     Ta tilde o
.It \e(:A      Ta \(:A     Ta dieresis A
.It \e(:E      Ta \(:E     Ta dieresis E
.It \e(:I      Ta \(:I     Ta dieresis I
.It \e(:O      Ta \(:O     Ta dieresis O
.It \e(:U      Ta \(:U     Ta dieresis U
.It \e(:a      Ta \(:a     Ta dieresis a
.It \e(:e      Ta \(:e     Ta dieresis e
.It \e(:i      Ta \(:i     Ta dieresis i
.It \e(:o      Ta \(:o     Ta dieresis o
.It \e(:u      Ta \(:u     Ta dieresis u
.It \e(:y      Ta \(:y     Ta dieresis y
.It \e(^A      Ta \(^A     Ta circumflex A
.It \e(^E      Ta \(^E     Ta circumflex E
.It \e(^I      Ta \(^I     Ta circumflex I
.It \e(^O      Ta \(^O     Ta circumflex O
.It \e(^U      Ta \(^U     Ta circumflex U
.It \e(^a      Ta \(^a     Ta circumflex a
.It \e(^e      Ta \(^e     Ta circumflex e
.It \e(^i      Ta \(^i     Ta circumflex i
.It \e(^o      Ta \(^o     Ta circumflex o
.It \e(^u      Ta \(^u     Ta circumflex u
.It \e(,C      Ta \(,C     Ta cedilla C
.It \e(,c      Ta \(,c     Ta cedilla c
.It \e(/L      Ta \(/L     Ta stroke L
.It \e(/l      Ta \(/l     Ta stroke l
.It \e(/O      Ta \(/O     Ta stroke O
.It \e(/o      Ta \(/o     Ta stroke o
.It \e(oA      Ta \(oA     Ta ring A
.It \e(oa      Ta \(oa     Ta ring a
.El
.\" PARAGRAPH
.Pp
Monetary:
.Bl -offset indent -column 10n 10n 10n
.It \e(Cs      Ta \(Cs     Ta Scandinavian
.It \e(Do      Ta \(Do     Ta dollar
.It \e(Po      Ta \(Po     Ta pound
.It \e(Ye      Ta \(Ye     Ta yen
.It \e(Fn      Ta \(Fn     Ta florin
.It \e(ct      Ta \(ct     Ta cent
.It \e(Eu      Ta \(Eu     Ta Euro character glyph
.It \e(eu      Ta \(eu     Ta Euro symbol
.El
.\" PARAGRAPH
.Pp
Greek letters:
.Bl -offset indent -column 10n 10n 10n
.It \e(*A      Ta \(*A     Ta Alpha
.It \e(*B      Ta \(*B     Ta Beta
.It \e(*G      Ta \(*G     Ta Gamma
.It \e(*D      Ta \(*D     Ta Delta
.It \e(*E      Ta \(*E     Ta Epsilon
.It \e(*Z      Ta \(*Z     Ta Zeta
.It \e(*Y      Ta \(*Y     Ta Eta
.It \e(*H      Ta \(*H     Ta Theta
.It \e(*I      Ta \(*I     Ta Iota
.It \e(*K      Ta \(*K     Ta Kappa
.It \e(*L      Ta \(*L     Ta Lambda
.It \e(*M      Ta \(*M     Ta Mu
.It \e(*N      Ta \(*N     Ta Nu
.It \e(*C      Ta \(*C     Ta Xi
.It \e(*O      Ta \(*O     Ta Omicron
.It \e(*P      Ta \(*P     Ta Pi
.It \e(*R      Ta \(*R     Ta Rho
.It \e(*S      Ta \(*S     Ta Sigma
.It \e(*T      Ta \(*T     Ta Tau
.It \e(*U      Ta \(*U     Ta Upsilon
.It \e(*F      Ta \(*F     Ta Phi
.It \e(*X      Ta \(*X     Ta Chi
.It \e(*Q      Ta \(*Q     Ta Psi
.It \e(*W      Ta \(*W     Ta Omega
.It \e(*a      Ta \(*a     Ta alpha
.It \e(*b      Ta \(*b     Ta beta
.It \e(*g      Ta \(*g     Ta gamma
.It \e(*d      Ta \(*d     Ta delta
.It \e(*e      Ta \(*e     Ta epsilon
.It \e(*z      Ta \(*z     Ta zeta
.It \e(*y      Ta \(*y     Ta eta
.It \e(*h      Ta \(*h     Ta theta
.It \e(*i      Ta \(*i     Ta iota
.It \e(*k      Ta \(*k     Ta kappa
.It \e(*l      Ta \(*l     Ta lambda
.It \e(*m      Ta \(*m     Ta mu
.It \e(*n      Ta \(*n     Ta nu
.It \e(*c      Ta \(*c     Ta xi
.It \e(*o      Ta \(*o     Ta omicron
.It \e(*p      Ta \(*p     Ta pi
.It \e(*r      Ta \(*r     Ta rho
.It \e(*s      Ta \(*s     Ta sigma
.It \e(*t      Ta \(*t     Ta tau
.It \e(*u      Ta \(*u     Ta upsilon
.It \e(*f      Ta \(*f     Ta phi
.It \e(*x      Ta \(*x     Ta chi
.It \e(*q      Ta \(*q     Ta psi
.It \e(*w      Ta \(*w     Ta omega
.It \e(+h      Ta \(+h     Ta theta variant
.It \e(+f      Ta \(+f     Ta phi variant
.It \e(+p      Ta \(+p     Ta pi variant
.It \e(+e      Ta \(+e     Ta epsilon variant
.It \e(ts      Ta \(ts     Ta sigma terminal
.El
.\" PARAGRAPH
.Pp
Special symbols:
.Bl -offset indent -column 10n 10n 10n
.It \e(de      Ta \(de     Ta degree
.It \e(ps      Ta \(ps     Ta paragraph
.It \e(sc      Ta \(sc     Ta section
.It \e(dg      Ta \(dg     Ta dagger
.It \e(dd      Ta \(dd     Ta double dagger
.It \e(ci      Ta \(ci     Ta circle
.It \e(ba      Ta \(ba     Ta bar
.It \e(bb      Ta \(bb     Ta broken bar
.It \e(co      Ta \(co     Ta copyright
.It \e(rg      Ta \(rg     Ta registered
.It \e(tm      Ta \(tm     Ta trademarked
.It \ee        Ta \e       Ta escape
.El 
.\" SECTION
.Sh PREDEFINED STRINGS
These are not recommended for use, as they differ across
implementations:
.Pp
Mathematical:
.Bl -offset indent -column 10n 10n 10n
.It \e*(Ba     Ta \*(Ba    Ta vertical bar
.It \e*(Ne     Ta \*(Ne    Ta not equal
.It \e*(Ge     Ta \*(Ge    Ta greater-than-equal
.It \e*(Le     Ta \*(Le    Ta less-than-equal
.It \e*(Gt     Ta \*(Gt    Ta greater-than
.It \e*(Lt     Ta \*(Lt    Ta less-than
.It \e*(Pm     Ta \*(Pm    Ta plus-minus
.It \e*(If     Ta \*(If    Ta infinity
.It \e*(Pi     Ta \*(Pi    Ta pi
.It \e*(Na     Ta \*(Na    Ta NaN
.El
.\" PARAGRAPH
.Pp
Special symbols:
.Bl -offset indent -column 10n 10n 10n
.It \e*(Ba     Ta \*(Ba    Ta vertical bar
.It \e*(Am     Ta \*(Am    Ta ampersand
.It \e*R       Ta \*R      Ta restricted mark
.It \e*(Tm     Ta \*(Tm    Ta trade mark
.El
.\" PARAGRAPH
.Pp
Enclosures:
.Bl -offset indent -column 10n 10n 10n
.It \e*q       Ta \*q      Ta double-quote
.It \e*(Rq     Ta \*(Rq    Ta right-double-quote
.It \e*(Lq     Ta \*(Lq    Ta left-double-quote
.It \e*(lp     Ta \*(lp    Ta right-parenthesis
.It \e*(rp     Ta \*(rp    Ta left-parenthesis
.El
.\" SECTION
.Sh COMPATIBILITY
This section documents compatibility of
.Nm
with older or existing versions of
.Xr groff 1 .
.Pp
The following render differently in
.Fl T Ns Ar ascii
output mode:
.Bd -ragged -offset indent
\e(ss, \e(nm, \e(nb, \e(nc, \e(ib, \e(ip, \e(pp, \e[sum], \e[product],
\e[coproduct], \e(gr, \e(-h, \e(a.
.Ed
.Pp
The following render differently in
.Fl T Ns Ar html
output mode:
.Bd -ragged -offset indent
\e(~=, \e(nb, \e(nc
.Ed
.Pp
Finally, the following have been omitted by being poorly documented or
having no known representation:
.Bd -ragged -offset indent
\e[radicalex], \e[sqrtex]
.Ed
.\" SECTION
.Sh SEE ALSO
.Xr mandoc 1
.\" SECTION
.Sh AUTHORS
The
.Nm
utility was written by 
.An Kristaps Dzonsons Aq kristaps@kth.se .