tmac/tmac.an: define .MR in a groff compatible way

groff 1.23.0 added .MR to its -man macro package.  The NEWS file states
that the inclusion of the macro "was prompted by its introduction to
Plan 9 from User Space's troff in August 2020."  From d32deab it seems
that the name for Plan 9 from User Space's implementation was suggested
by groff maintainer G. Brandon Robinson.

Not sure if the intention was to make these definitions compatible, but
it would be nice if they were.

Currently, Plan 9 from User Space's .MR expects its second argument to
be parenthesized.  groff's .MR does not.  This results in extra
parentheses appearing in manual references when viewing Plan 9 from User
Space's manual pages on a system using groff.

1 files changed, 21 insertions, 21 deletions

diff --git a/man/man1/acme.1 b/man/man1/acme.1
index bb2c89d6..6ed8050b 100644
--- a/man/man1/acme.1
+++ b/man/man1/acme.1
@@ -45,7 +45,7 @@ The interactive interface uses the keyboard and mouse; external programs
 use a set of files served by
 .IR acme ;
 these are discussed in
-.MR acme (4) .
+.MR acme 4 .
 .PP
 Any named
 .I files
@@ -86,7 +86,7 @@ The
 option instructs
 .I acme
 to use FUSE (see
-.MR 9pfuse (4) )
+.MR 9pfuse 4 )
 to mount itself at
 .IR mtpt .
 (Experimental.)
@@ -98,10 +98,10 @@ windows are in two parts: a one-line
 above a multi-line
 .IR body .
 The body typically contains an image of a file, as in
-.MR sam (1) ,
+.MR sam 1 ,
 or the output of a
 program, as in an
-.MR rio (1)
+.MR rio 1
 window.
 The tag contains a number of
 blank-separated words, followed by a vertical bar character, followed by anything.
@@ -118,9 +118,9 @@ a slash.
 .SS Scrolling
 Each window has a scroll bar to the left of the body.
 The scroll bar behaves much as in
-.MR sam (1)
+.MR sam 1
 or
-.MR rio (1)
+.MR rio 1
 except that scrolling occurs when the button is pressed, rather than released,
 and continues
 as long as the mouse button is held down in the scroll bar.
@@ -131,7 +131,7 @@ down the scroll bar speeds up the rate of scrolling.
 .B -r
 reverses the scrolling behavior of buttons 1 and 3, to behave
 more like
-.MR xterm (1) .)
+.MR xterm 1 .)
 .SS Layout
 .I Acme
 windows are arranged in columns.  By default, it creates two columns when starting;
@@ -164,7 +164,7 @@ pre-loads them with useful commands.
 Also, the tag across the top maintains a list of executing long-running commands.
 .SS Typing
 The behavior of typed text is similar to that in
-.MR rio (1)
+.MR rio 1
 except that the characters are delivered to the tag or body under the mouse; there is no
 `click to type'.
 (The experimental option
@@ -172,7 +172,7 @@ except that the characters are delivered to the tag or body under the mouse; the
 causes typing to go to the most recently clicked-at or made window.)
 The usual backspacing conventions apply.
 As in
-.MR sam (1)
+.MR sam 1
 but not
 .IR rio ,
 the ESC key selects the text typed since the last mouse action,
@@ -249,7 +249,7 @@ is identified by the context of the command.
 These error windows are created when needed.
 .SS "Mouse button 1
 Mouse button 1 selects text just as in
-.MR sam (1)
+.MR sam 1
 or
 .IR rio (1) ,
 including the usual double-clicking conventions.
@@ -305,7 +305,7 @@ by default.
 .TP
 .B Edit
 Treat the argument as a text editing command in the style of
-.MR sam (1) .
+.MR sam 1 .
 The full
 .B Sam
 language is implemented except for the commands
@@ -379,7 +379,7 @@ With no arguments,
 prints the supplementary list.
 This command is largely superseded by plumbing
 (see
-.MR plumb (7) ).
+.MR plumb 7 ).
 .TP
 .B Indent
 Set the autoindent mode according to the argument:
@@ -507,7 +507,7 @@ If the text indicated with button 2 is not a recognized built-in, it is executed
 a shell command.  For example, indicating
 .B date
 with button 2 runs
-.MR date (1) .
+.MR date 1 .
 The standard
 and error outputs of commands are sent to the error window associated with
 the directory from which the command was run, which will be created if
@@ -525,7 +525,7 @@ in a window containing
 executing
 .B mk
 will run
-.MR mk (1)
+.MR mk 1
 in
 .BR /home/rob/sam ,
 producing output in a window labeled
@@ -539,12 +539,12 @@ and
 .B $winid
 set to the window's id number
 (see
-.MR acme (4) ).
+.MR acme 4 ).
 .PP
 The environment variable
 .B $acmeshell
 determines which shell is used to execute such commands; the
-.MR rc (1)
+.MR rc 1
 shell is used by default.
 .SS "Mouse button 3
 Pointing at text with button 3 instructs
@@ -574,7 +574,7 @@ command adds directories to the standard list.)
 .PP
 If the text begins with a colon, it is taken to be an address, in
 the style of
-.MR sam (1) ,
+.MR sam 1 ,
 within the body of the window containing the text.
 The address is evaluated, the resulting text highlighted, and the mouse moved to it.
 Thus, in
@@ -649,7 +649,7 @@ then execute
 clicking button 1 while 2 is held down.
 .PP
 When an external command (e.g.
-.MR echo (1) )
+.MR echo 1 )
 is executed this way, the extra argument is passed as expected and an
 environment variable
 .B $acmeaddr
@@ -682,7 +682,7 @@ window and runs a
 (default
 .BR $SHELL )
 in it, turning the window into something analogous to an
-.MR 9term (1)
+.MR 9term 1
 window.
 Executing text in a
 .I win
@@ -691,7 +691,7 @@ window with button
 .BR Send .
 .I Win
 windows follow the same scrolling heuristic as in
-.MR 9term (1) :
+.MR 9term 1 :
 the window scrolls on output only if the window is displaying the end of the buffer.
 .PP
 .I Awd
@@ -779,7 +779,7 @@ MIPS-specific binaries for applications
 .br
 .B \*9/bin/awd
 .SH SEE ALSO
-.MR acme (4)
+.MR acme 4
 .br
 Rob Pike,
 .I