Texinfo からの借用

[201] DanC が明言しているように最初に追加された語句化内容要素群は基本的に Texinfo からの借用です (>>161)。

[202] DanC が参照した Texinfo のドキュメントからの引用がありますが >>158、 改めて当時のドキュメントを確認してみます。 DanC が参照したものがどのように入手したどのドキュメントだったのかまでは不明ですが、 当時の GNU Texinfo のドキュメントは GNU Emacs に同梱されて配布されていて、現在も近い時期のものが残っています。

• [203] emacs-history/ftp.gnu.org/old-gnu/emacs/emacs-18.59.tar.gz at sources · larsbrinkhoff/emacs-history · GitHub, 2024-09-30T13:44:44.000Z https://github.com/larsbrinkhoff/emacs-history/blob/sources/ftp.gnu.org/old-gnu/emacs/emacs-18.59.tar.gz

[204] >>203 のファイルの中身のファイルの日付は、 ChangeLog が1992-10-31となっています。他はそれより古いファイルです。

[205] man/texinfo.texi という日付が1990-09-26のファイルがあります。 Texinfo 1.1 と題されており、

This file documents Texinfo, a documentation system that uses a single
source file to produce both on-line help and a printed manual.  

This is edition 1.1 of the Texinfo documentation, and is for the Texinfo
that is distributed as part of Version 18 of GNU Emacs.

Copyright (C) 1988 Free Software Foundation, Inc.

@center The GNU Documentation Format
@sp 2
@center by Richard M. Stallman and Robert J. Chassell
@sp 2
@center Edition 1.1
@sp 2
@center May 1988

と冒頭にあります。

[206] その内容を見ると、 DanC の引用とよく似た箇所があります。 引用した部分以外にも多くの説明があります。分量が多いですが、 重要なので引いておきます。

[207] いわゆる論理要素に相当するもの:

@section Specifying Definitions, Files, Commands etc.
@cindex Highlighting
@cindex Specifying commands, files and the like
@cindex Definitions, specifying them within text
@cindex Commands, specifying them within text
@cindex Files, specifying them within text

Texinfo has a variety of commands for specifying just what kind of object a
piece of text refers to.  Metasyntactic variables, for example, are marked
by one @@-command and code by another.  Texinfo uses this information to
determine how to highlight the text.  Since the pieces of text are labelled
by commands that tell what kind of object they are, it is easy to change
the way Texinfo formats and typesets such text.  For example, code is
usually illustrated in a typewriter font, but it would be easy to change
the way Texinfo highlights code to use another font.  This change would not
effect how metasyntatic variables are highlighted.  If straight typesetting
commands were used in the body of the file, you would have to check every
single occurrence to make sure that you were changing code and not
something else that should not be changed.

In addition, the commands can be used to generate useful information from
the file, such as lists of functions or file names.  It is possible, for
example, to write code in Emacs Lisp (or a keyboard macro) to insert an
index entry after every paragraph that contains the text labelled by a
specified command.  You could do this to construct an index of functions if
you had not already made the entries.

The commands serve a variety of purposes:

@table @code
@item @@code
Indicates text that is a literal example of a piece of a program.@refill

@item @@samp
Indicates text that is a literal example of a sequence of characters.@refill

@item @@file
Indicates the name of a file.@refill

@item @@kbd
Indicates the names of keys on the keyboard or characters you type.@refill

@item @@key
Used for the conventional name for a key on a keyboard.@refill

@item @@ctrl
Indicates an ASCII control character.

@item @@var
Indicates a metasyntactic variable.

@item @@dfn
Indicates the introductory or defining use of a term.

@item @@cite
Indicates the name of a book.
@end table



@menu
* Code::	A literal example of a piece of a program.
* Samp::	A literal example of a sequence of characters.
* File::	The name of a file.
* Kbd::		The names of keys or else characters you type.
* Key::		The conventional name for a key on a keyboard.
* Ctrl::	Indicates the ASCII control character.
* Var::		A variable.
* Dfn::		The introductory or defining use of a term.
* Cite::	The name of a book.
@end menu

@node     Code, Samp, , Specifying
@comment  node-name,  next,  previous,  up
@subsection @@code
@findex code

@code{@@code} is used to indicate text that is a piece of a program which
consists of entire syntactic tokens.  The text follows, enclosed in braces.

For example, @code{@@code} is used for an expression in a program, the name
of a variable or function used in a program, or a keyword.  @code{@@code}
is not used for a piece of a token, such as when speaking about the
characters used in a token; for example, when you are explaining what
letters or printable symbols can be used in the names of functions.  It is
also not used for input to programs unless the input is written in a
language that is like a programming language.  For example, it is not used
for the single character commands of GNU Emacs although it is used for the
names of Emacs Lisp functions that the keyboard commands invoke.

You should also @code{@@code} for command names in command languages that
resemble programming languages, such as Texinfo or the shell.  Note,
however, that @code{@@code} is not used for options such as @samp{-c} when
such options stand alone.  There is some argument as to whether an entire
shell command incorporating an option should be written using @code{@@code}
or @code{@@samp}.@refill

It is an error to alter the case of a word inside an @code{@@code}
command.  This is a particularly insidious error if the language being
documented is case sensitive.  If the command is @code{printf}, then
@code{Printf} is a misspelling.  If you do not like having such a command
with lower case at the beginning of a sentence, you may wish to rearrange
the sentence.

In the printed manual, @code{@@code} puts the argument in bold face.
In the Info file, it uses `@dots{}' quotation.  For example:

@example
To compare two files, showing text inserted or removed, use @@code@{diff@}.
@end example

@noindent
produces

@quotation
To compare two files, showing text inserted or removed, use @code{diff}.
@end quotation

@iftex
In the Info file, it looks like this:

@example
@dots{}, use `diff'
@end example
@end iftex

@node     Samp, File, Code, Specifying
@comment  node-name,  next,  previous,  up
@subsection @@samp
@findex samp

@code{@@samp} is used to indicate text that is a literal example of a
sequence of characters in a file, string, pattern, etc.  The text follows,
enclosed in braces.  The argument appears within `@dots{}' quotation in
both the Info file and the printed manual; in addition, it is printed in a
fixed-width font.

@example
To match @@samp@{foo@} at the end of the line, use the regexp @@samp@{foo$@}.
@end example

@noindent
produces

@quotation
To match @samp{foo} at the end of the line, use the regexp @samp{foo$}.
@end quotation

Any time you are referring to single characters, you should use @code{@@samp}
unless @code{@@kbd} is more appropriate.  Basically, @code{@@samp} is a
catchall for whatever is not covered by @code{@@code}, @code{@@file},
@code{@@kbd}.

Punctuation marks that are part of the English text that surrounds the
strings you are specifying are @emph{never} included within the braces.  In
the following sentence, for example, the commas and period are outside of
the braces:

@example
A symbol name ends in @@samp@{a@}, @@samp@{b@}, or @@samp@{c@}.
@end example

@node     File, Kbd, Samp, Specifying
@comment  node-name,  next,  previous,  up
@subsection @@file
@findex file

@code{@@file} is used to indicate text that is the name of a file or
directory.  Currently, it is equivalent to @code{@@samp} in its effects on
the output.  For example,@refill

@example
The @@file@{.el@} files are in 
the @@file@{/gnu/emacs/lisp@} directory.
@end example

@noindent
produces

@quotation
The @file{.el} files are in 
the @file{/gnu/emacs/lisp} directory.
@end quotation

@node     Kbd, Key, File, Specifying
@comment  node-name,  next,  previous,  up
@subsection @@kbd
@findex kbd

@code{@@kbd} is used much like @code{@@code}.  The difference is that
@code{@@kbd} is for names of keys on the keyboard, or of characters you can
type.  For example, to refer to the command @kbd{M-a}, you would use

@example
@@kbd@{M-a@}
@end example

@noindent
and to refer to @kbd{M-x shell}, you would use

@example
@@kbd@{M-x shell@}
@end example

The @code{@@kbd} command has the same effect as @code{@@code} in Info,
but may produce a different font in a printed manual.@refill

You can embed another @@-command inside the braces of a @code{@@kbd}
command.  This is the way to describe a command that would be described
more verbosely as ``press an @samp{r} and then press the @key{RET} key'':

@example
@@kbd@{r @@key@{RET@}@}  
@end example

@noindent
This produces: @kbd{r @key{RET}}

You also use the @code{@@kbd} command if you are spelling out the letters
you type; for example:

@example
To give the @@code@{logout@} command, 
type the characters @@kbd@{l o g o u t @@key@{RET@}@}.
@end example

@noindent
This produces

@quotation
To give the @code{logout} command, 
type the characters @kbd{l o g o u t @key{RET}}.
@end quotation

@node     Key, Ctrl, Kbd, Specifying
@comment  node-name,  next,  previous,  up
@subsection @@key
@findex key

@code{@@key} is used for the conventional name for a key on a keyboard, as
in

@example
@@key@{RET@}
@end example

Often, @code{@@key} is used within the argument of a @code{@@kbd}
command, whenever the sequence of characters to be typed includes one or
more keys that are described by name.@refill

For example, to produce @kbd{C-x @key{ESC}} you would use 

@example
@@kbd@{C-x @@key@{ESC@}@}
@end example


The recommended names to use for keys are in upper case and are

@table @t
@item SPC
Space.
@item RET
Return.
@item LFD
Linefeed.
@item TAB
Tab.
@item BS
Backspace.
@item ESC
Escape.
@item DEL
Delete.
@item SFT
Shift.
@item CTL
Control.
@item META
Meta.
@end table

There are subtleties to handling words like `meta' or `ctrl' which are
names of shift keys.  When mentioning a character in which the shift key is
used, such as @kbd{Meta-a}, use the @code{@@kbd} command alone without the
@code{@@key} command, but when you are referring to shift key in isolation,
use the @code{@@key} command.  For example, you would use
@samp{@@kbd@{Meta-a@}} to produce @kbd{Meta-a} and @samp{@@key@{META@}} to
produce @key{META}.

@node     Ctrl, Var, Key, Specifying
@comment  node-name,  next,  previous,  up
@subsection @@ctrl
@findex ctrl

@code{@@ctrl} is used to describe an ASCII control character.  The pattern
of usage is @code{@@ctrl@{@var{ch}@}}, where @var{ch} is an ASCII character
whose control-equivalent is wanted.  Thus, you put in an @samp{f} when
you want to indicate a @samp{control-f}

Thus, to specify @samp{control-f}, you would enter

@example
@@ctrl@{f@}
@end example

@noindent
which produces

@quotation
@ctrl{f}
@end quotation

In the Info file, this generates the specified control character, output
literally into the file.  This is done so a user can copy the specified
control character (along with whatever else he or she wants) into another
Emacs buffer and use it.  Since the `control-h',`control-i', and
`control-j' characters are formatting characters, they should not be
indicated this way.@refill

In a printed manual, this generates text to describe or identify that
control character: an uparrow followed by the character @var{ch}.

@node     Var, Dfn, Ctrl, Specifying
@comment  node-name,  next,  previous,  up
@subsection @@var
@findex var

@code{@@var} is used to indicate metasyntactic variables.  A metasyntactic
variable is something that stands for another piece of text.  You would use
a metasyntactic variable in the documentation of a function to describe the
arguments that are passed to that function.

@code{@@var} is not used for names of particular variables in programming
languages.  For example, the Texinfo variable @code{texinfo-tex-command} is
not a metasyntactic variable.

Its effect in the Info file is to upcase the argument; in the printed
manual, to italicize it.  Example:

@example
To delete file @@var@{filename@}, type @@code@{rm @@var@{filename@}@}.
@end example

@noindent
produces

@quotation
To delete file @var{filename}, type @code{rm @var{filename}}.
@end quotation

In some documentation styles, metasyntactic variables are shown with angle
brackets, for example: 

@example
@dots{}, type rm <filename>
@end example

@node     Dfn, Cite, Var, Specifying
@comment  node-name,  next,  previous,  up
@subsection @@dfn
@findex dfn

@code{@@dfn} is used to identify the introductory or defining use of a
technical term.  The command should be used only in a passage whose purpose
is to introduce a term which will be used again or which the reader ought
to know.  Mere passing mention of a term for the first time doesn't deserve
@code{@@dfn}.  It generates italics in the printed manual, and double
quotation marks in the Info file.  Example:

@example
Getting rid of a file is called @@dfn@{deleting@} it.
@end example

@noindent
produces

@quotation
Getting rid of a file is called @dfn{deleting} it.
@end quotation

@node     Cite, , Dfn, Specifying
@comment  node-name,  next,  previous,  up
@subsection @@cite
@findex cite

@code{@@cite} is used for the name of a book.  It produces italics
in the printed manual, and quotation marks in the Info file.

[208] 強調と物理要素に相当するもの:

@node     Emphasis, , Dots Bullets Tex, Marking Text
@comment  node-name,  next,  previous,  up
@section Emphasizing Text
@cindex  Emphasizing text

Usually, Texinfo changes the font automatically to mark words in the text
according to what category the words belong to.  The @code{@@code} command,
for example, does this.  Most often, this is the best way to mark specified
words.  However, sometimes you will want to emphasize text directly.
Texinfo has two ways to do this: commands that tell Texinfo to emphasize
the text but leave the method to the program, and commands that specify the
font to use.  The first method is generally the best and it makes it
possible to change the style of a document without have to re-edit it line
by line.

@menu
* Emph and Strong::	Emphasizing text.
* Fonts::		Selecting italic, bold or typewriter fonts.
@end menu

@node     Emph and Strong, Fonts, , Emphasis
@comment  node-name,  next,  previous,  up
@subsection @@emph and @@strong
@findex emph
@findex strong

@code{@@emph} and @code{@@strong} are two forms of emphasis.  @code{@@strong}
is stronger.

In printed output, @code{@@emph} produces @emph{italics} and @code{@@strong}
produces @strong{bold}.

In the Info file, both of these commands put asterisks around the
argument.

@node     Fonts, , Emph and Strong, Emphasis
@comment  node-name,  next,  previous,  up
@subsection @@i,  @@b and @@t
@findex i (italic font)
@findex b (bold font)
@findex t (typewriter font)

These three commands specify font changes in the printed manual and have no
effect in the Info file.  @code{@@i} requests @i{italic} font (in some
versions of @TeX{}, a slanted font is used), @code{@@b} requests @b{bold}
face, and @code{@@t} requests the @t{fixed-width} font used by
@code{@@kbd}.  All three commands apply to an argument that follows,
surrounded by braces.@refill

If possible, you should avoid using these three commands.  If you find a
need to use one, it probably indicates a lack in the Texinfo language.

[209] この詳細な説明が全文 HTML の要素一覧にも引かれていれば、 その後の展開もまた違ったものになっていたでしょうね。

LaTeX からの借用

[181] em と tt は、その要素名を LaTeX から借用したと考えられます (>>148 >>179)。

• [183] CTAN: /tex-archive/obsolete/macros/latex209/distribs, 2024-09-30T12:43:22.000Z https://ctan.org/tex-archive/obsolete/macros/latex209/distribs
  • [184] 2024-09-30T12:43:35.200Z https://mirrors.ctan.org/obsolete/macros/latex209/distribs/latex209.tar.gz

[185] >>184 に 1997-01-22 01:00 付の latex209.tar.gz があります。 中身のファイルの日付は1992-03-19, 1992-03-20, 1992-04-01のいずれかの正時に揃っています。 どうにも不自然ですが、1997-01-22に過去のファイルを集めて作成したtar玉なのでしょう。

[186] DanC が参照したものが何だったのか、 LaTeX という以外に情報がありませんが、 この tar玉の中身とそう遠くはないものだろうと期待されます。

[187] general/latex.tex という1992-04-01のファイル LATEX VERSION 2.09 <25 March 1992> には、

%     ****************************************
%     *           COMMAND LIST               *
%     ****************************************

%  IN DOCUMENT :
%    FONT SELECTION:
%         SIZE: \normalsize \small \footnotesize \scriptsize \tiny
%               \large \Large \LARGE \huge \Huge
%         STYLE: \bf \it \rm \sl \ss \tt \mit[math mode only]

とあります。

[188] general/sfonts.tex という1992-03-19のファイル File SFONTS - Version of 25 November 1991 には、

% protected font names
\def\rm{\protect\prm}
\def\it{\protect\pit}
\def\bf{\protect\pbf}
\def\tt{\protect\ptt}
\def\sl{\@subfam\sl\it}
\def\sf{\@subfam\sf\rm}
\def\sc{\protect\psc}
 
\def\em{\protect\pem{}}
\def\pem{\relax\ifdim \fontdimen\@ne\font >\z@ \rm \else \it \fi}

とあります。

[189] general/lfonts.tex という1992-03-19のファイル File LFONTS - Version of 25 November 1991 には、

% \em is defined to be \it inside an unslanted style and \rm inside a
% slanted style.  An \em command in a section title will produce a \pem
% command in the table of contents.
%

\def\em{\protect\pem{}}
\def\pem{\relax\ifdim \fontdimen\@ne\font >\z@ \rm \else \it \fi}

% protected font names
\def\rm{\protect\prm}
\def\it{\protect\pit}
\def\bf{\protect\pbf}
\def\sl{\protect\psl}
\def\sf{\protect\psf}
\def\sc{\protect\psc}
\def\tt{\protect\ptt}

とあります。

[190] general/local.tex という1992-03-19のファイル local.tex -- released 26 February 1992 には、

Table~\ref{tab:fonts}
tells, for every type size, to which class of fonts each type style
belongs.  For example, in 14pt type, \verb|\bf| uses a preloaded
font and the other five type-style commands use load-on-demand fonts.
Roman (\verb|\rm|) and math italic (\verb|\mit|) fonts are all
preloaded; the \hbox{\verb|\em|} declaration uses either italic
(\verb|\it|) or roman.

とあってフォントとサイズの表があります。

[191] 以上、 DanC の引用 (>>138) と若干違うのが気になりますが、 \tt を含む7種類のフォントスタイルがあり、 \em が \it または \rm のどちらかとして実装されていることがわかります。

[192] local.tex には \tt や \em が大量に使われているので、 いくつか用法を見ておきましょう。

[193] \em で書名を強調

computers at SRC. It is not about \LaTeX\ itself, which is described by
the manual---{\em \LaTeX: A Document Preparation System}, published by
Addison-Wesley, available at fine book stores everywhere.

[194] \em で入力する文字列を強調、 \tt でファイル名

(You must type the space followed by the period at the end.  This
and all other Ultrix commands are ended by typing {\em return}.)
A copy of the file \mbox{\tt sample.tex} is now in your current
directory; you can edit it just like any other file.  If you destroy or

[195] \em で文書名を強調

You must use a text editor to prepare an input file for \LaTeX. The
document {\em Welcome to SRC\/} describes the text editors available
at SRC.  The easiest way to start learning about \LaTeX\ is by 

[196] \em で打鍵列を強調

because it is printing a seemingly unending string of uninformative
error messages, type {\em Control-C\/} (press $C$ while holding down
the key labeled {\em CTRL\/}).  This will make \LaTeX\ stop as if it

[197] \em で文中の語を強調、 \tt で LaTeX の機能名

Except for these differences, a \SLiTeX\ input file prepared for the
ordinary {\tt slides} style {\em should\/} work with the {\tt
ps-slides} style.  There are probably some \SLiTeX\ commands that will

[198] \em で可変部分を強調、 \tt で実行するコマンド

\begin{quote} \tt
     aptex -Pcolor {\em file-name}.dvi
\end{quote}

[199] 他にも用例が多数あります。 \tt はおおむね現在の HTML の code の役割で使われています。 \em はいろいろな意味で強調、 周りとの区別を表すために使われていて、現在の HTML でいえば em, strong, var, kbd など幅広く応用されています。

[200] これを現在視点から見ると code があるのに tt は要らなそうにも感じますが、 当時の code の意味と比べると、 \tt がないと困りそうです。 @file が省かれて \tt が採用された理由もこの辺りにあるのかもしれません。