Fully support explicit tagging of .Sh and .Ss.

[mandoc.git] / eqn.7

diff --git a/eqn.7 b/eqn.7
index 182fd4cfd719ae563a6d4012d3dfb926287a674f..e164e8fb651c72cb46eedcc5c100b5914815bc5b 100644 (file)
--- a/eqn.7
+++ b/eqn.7
@@ -1,4 +1,4 @@
-.\"    $Id: eqn.7,v 1.33 2015/01/29 00:33:57 schwarze Exp $
+.\"    $Id: eqn.7,v 1.39 2020/01/10 11:55:04 schwarze Exp $

 .\"
 .\" Copyright (c) 2011 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2014 Ingo Schwarze <schwarze@openbsd.org>
 .\"
 .\" Copyright (c) 2011 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2014 Ingo Schwarze <schwarze@openbsd.org>


@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"

-.Dd $Mdocdate: January 29 2015 $
+.Dd $Mdocdate: January 10 2020 $

 .Dt EQN 7
 .Os
 .Sh NAME
 .Dt EQN 7
 .Os
 .Sh NAME


@@ -44,59 +44,47 @@ specification (see
 .Sx SEE ALSO
 for references).
 .Pp
 .Sx SEE ALSO
 for references).
 .Pp

-Equations within
-.Xr mdoc 7
-or
-.Xr man 7
-documents are enclosed by the standalone
-.Sq \&.EQ
-and
-.Sq \&.EN
-tags.
-Equations are multi-line blocks consisting of formulas and control
-statements.
-.Sh EQUATION STRUCTURE
-Each equation is bracketed by
-.Sq \&.EQ
-and
-.Sq \&.EN
-strings.
-.Em Note :
-these are not the same as
-.Xr roff 7
-macros, and may only be invoked as
-.Sq \&.EQ .
+An equation starts with an input line containing exactly the characters
+.Sq \&.EQ ,
+may contain multiple input lines, and ends with an input line
+containing exactly the characters
+.Sq \&.EN .
+Equivalently, an equation can be given in the middle of a single
+text input line by surrounding it with the equation delimiters
+defined with the
+.Cm delim
+statement.

 .Pp
 The equation grammar is as follows, where quoted strings are
 case-sensitive literals in the input:
 .Bd -literal -offset indent
 eqn     : box | eqn box
 box     : text
 .Pp
 The equation grammar is as follows, where quoted strings are
 case-sensitive literals in the input:
 .Bd -literal -offset indent
 eqn     : box | eqn box
 box     : text

-        | \*q{\*q eqn \*q}\*q
-        | \*qdefine\*q text text
-        | \*qndefine\*q text text
-        | \*qtdefine\*q text text
-        | \*qgfont\*q text
-        | \*qgsize\*q text
-        | \*qset\*q text text
-        | \*qundef\*q text
-        | \*qsqrt\*q box
+        | \(dq{\(dq eqn \(dq}\(dq
+        | \(dqdefine\(dq text text
+        | \(dqndefine\(dq text text
+        | \(dqtdefine\(dq text text
+        | \(dqgfont\(dq text
+        | \(dqgsize\(dq text
+        | \(dqset\(dq text text
+        | \(dqundef\(dq text
+        | \(dqsqrt\(dq box

         | box pos box
         | box mark
         | box pos box
         | box mark

-        | \*qmatrix\*q \*q{\*q [col \*q{\*q list \*q}\*q ]*
-        | pile \*q{\*q list \*q}\*q
+        | \(dqmatrix\(dq \(dq{\(dq [col \(dq{\(dq list \(dq}\(dq]* \(dq}\(dq
+        | pile \(dq{\(dq list \(dq}\(dq

         | font box
         | font box

-        | \*qsize\*q text box
-        | \*qleft\*q text eqn [\*qright\*q text]
-col     : \*qlcol\*q | \*qrcol\*q | \*qccol\*q | \*qcol\*q
-text    : [^space\e\*q]+ | \e\*q.*\e\*q
-pile    : \*qlpile\*q | \*qcpile\*q | \*qrpile\*q | \*qpile\*q
-pos     : \*qover\*q | \*qsup\*q | \*qsub\*q | \*qto\*q | \*qfrom\*q
-mark   : \*qdot\*q | \*qdotdot\*q | \*qhat\*q | \*qtilde\*q | \*qvec\*q
-        | \*qdyad\*q | \*qbar\*q | \*qunder\*q
-font    : \*qroman\*q | \*qitalic\*q | \*qbold\*q | \*qfat\*q
+        | \(dqsize\(dq text box
+        | \(dqleft\(dq text eqn [\(dqright\(dq text]
+col     : \(dqlcol\(dq | \(dqrcol\(dq | \(dqccol\(dq | \(dqcol\(dq
+text    : [^space\e\(dq]+ | \e\(dq.*\e\(dq
+pile    : \(dqlpile\(dq | \(dqcpile\(dq | \(dqrpile\(dq | \(dqpile\(dq
+pos     : \(dqover\(dq | \(dqsup\(dq | \(dqsub\(dq | \(dqto\(dq | \(dqfrom\(dq
+mark   : \(dqdot\(dq | \(dqdotdot\(dq | \(dqhat\(dq | \(dqtilde\(dq | \(dqvec\(dq
+        | \(dqdyad\(dq | \(dqbar\(dq | \(dqunder\(dq
+font    : \(dqroman\(dq | \(dqitalic\(dq | \(dqbold\(dq | \(dqfat\(dq

 list    : eqn
 list    : eqn

-        | list \*qabove\*q eqn
+        | list \(dqabove\(dq eqn

 space   : [\e^~ \et]
 .Ed
 .Pp
 space   : [\e^~ \et]
 .Ed
 .Pp


@@ -125,7 +113,7 @@ int (integral), sum (summation), grad (gradient), del (vector
 differential), times (multiply), cdot (center-dot), nothing (zero-width
 space), approx (approximately equals), prime (prime), half (one-half),
 partial (partial differential), inf (infinity), >> (much greater), <<
 differential), times (multiply), cdot (center-dot), nothing (zero-width
 space), approx (approximately equals), prime (prime), half (one-half),
 partial (partial differential), inf (infinity), >> (much greater), <<

-(much less), \-> (left arrow), <\- (right arrow), +\- (plus-minus), !=
+(much less), <\- (left arrow), \-> (right arrow), +\- (plus-minus), !=

 (not equal), == (equivalence), <= (less-than-equal), and >=
 (more-than-equal).
 The character escape sequences documented in
 (not equal), == (equivalence), <= (less-than-equal), and >=
 (more-than-equal).
 The character escape sequences documented in


@@ -146,7 +134,7 @@ is used as the delimiter for the value
 .Ar val .
 This allows for arbitrary enclosure of terms (not just quotes), such as
 .Pp
 .Ar val .
 This allows for arbitrary enclosure of terms (not just quotes), such as
 .Pp

-.D1 Cm define Ar foo 'bar baz'
+.D1 Cm define Ar foo \(aqbar baz\(aq

 .D1 Cm define Ar foo cbar bazc
 .Pp
 It is an error to have an empty
 .D1 Cm define Ar foo cbar bazc
 .Pp
 It is an error to have an empty


@@ -166,8 +154,8 @@ created.
 Definitions can create arbitrary strings, for example, the following is
 a legal construction.
 .Bd -literal -offset indent
 Definitions can create arbitrary strings, for example, the following is
 a legal construction.
 .Bd -literal -offset indent

-define foo 'define'
-foo bar 'baz'
+define foo \(aqdefine\(aq
+foo bar \(aqbaz\(aq

 .Ed
 .Pp
 Self-referencing definitions will raise an error.
 .Ed
 .Pp
 Self-referencing definitions will raise an error.


@@ -178,6 +166,25 @@ statement is a synonym for
 while
 .Cm tdefine
 is discarded.
 while
 .Cm tdefine
 is discarded.

+.It Cm delim
+This statement takes a string argument consisting of two bytes,
+to be used as the opening and closing delimiters for equations
+in the middle of text input lines.
+Conventionally, the dollar sign is used for both delimiters,
+as follows:
+.Bd -literal -offset indent
+\&.EQ
+delim $$
+\&.EN
+An equation like $sin pi = 0$ can now be entered
+in the middle of a text input line.
+.Ed
+.Pp
+The special statement
+.Cm delim off
+temporarily disables previously declared delimiters and
+.Cm delim on
+reenables them.

 .It Cm gfont
 Set the default font of subsequent output.
 Its syntax is as follows:
 .It Cm gfont
 Set the default font of subsequent output.
 Its syntax is as follows:


@@ -434,7 +441,7 @@ implementation (including GNU troff).
 .Bl -dash -compact
 .It
 The text string
 .Bl -dash -compact
 .It
 The text string

-.Sq \e\*q
+.Sq \e\(dq

 is interpreted as a literal quote in troff.
 In mandoc, this is interpreted as a comment.
 .It
 is interpreted as a literal quote in troff.
 In mandoc, this is interpreted as a comment.
 .It


@@ -470,7 +477,7 @@ commands are also ignored.
 .%T System for Typesetting Mathematics
 .%J Communications of the ACM
 .%V 18
 .%T System for Typesetting Mathematics
 .%J Communications of the ACM
 .%V 18

-.%P 151\(en157
+.%P pp. 151\(en157

 .%D March, 1975
 .Re
 .Rs
 .%D March, 1975
 .Re
 .Rs