[7275] Improve some comments

[trueroad]

Revision: 7275
          http://svn.sv.gnu.org/viewvc/?view=rev&root=texinfo&revision=7275
Author:   trueroad
Date:     2016-07-27 14:35:22 +0000 (Wed, 27 Jul 2016)
Log Message:
-----------
Improve some comments

Modified Paths:
--------------
    trunk/ChangeLog
    trunk/doc/texinfo.tex

Modified: trunk/ChangeLog
===================================================================
--- trunk/ChangeLog     2016-07-23 13:51:07 UTC (rev 7274)
+++ trunk/ChangeLog     2016-07-27 14:35:22 UTC (rev 7275)
@@ -1,3 +1,9 @@
+2016-07-27  Masamichi Hosoda  <address@hidden>
+
+       * doc/texinfo.tex:
+       Improve some Unicode and XeTeX, LuaTeX related comments
+       by Werner Lemberg's suggestion.
+
 2016-07-23  Gavin Smith  <address@hidden>
 
        * doc/texinfo.tex (\indexdummies): Use \definedummyletter\@ 

Modified: trunk/doc/texinfo.tex
===================================================================
--- trunk/doc/texinfo.tex       2016-07-23 13:51:07 UTC (rev 7274)
+++ trunk/doc/texinfo.tex       2016-07-27 14:35:22 UTC (rev 7275)
@@ -3,7 +3,7 @@
 % Load plain if necessary, i.e., if running under initex.
 \expandafter\ifx\csname fmtname\endcsname\relax\input plain\fi
 %
-\def\texinfoversion{2016-07-23.14}
+\def\texinfoversion{2016-07-27.14}
 %
 % Copyright 1985, 1986, 1988, 1990, 1991, 1992, 1993, 1994, 1995,
 % 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
@@ -1543,28 +1543,28 @@
   %
   \ifnum\strcmp{\the\XeTeXversion\XeTeXrevision}{0.99996}>-1
     % TeX Live 2016 contains XeTeX 0.99996 and xdvipdfmx 20160307.
-    % It can be used `dvipdfmx:config' special (from TeX Live SVN r40941).
-    % For avoiding PDF destination name replacement, we use the special
-    % instead of xdvipdfmx commandline option `-C 0x0010'.
+    % It can use the `dvipdfmx:config' special (from TeX Live SVN r40941).
+    % For avoiding PDF destination name replacement, we use this special
+    % instead of xdvipdfmx's command line option `-C 0x0010'.
     \special{dvipdfmx:config C 0x0010}
-    % XeTeX 0.99995+ contains xdvipdfmx 20160307+.
-    % It can handle Unicode destination name for PDF.
+    % XeTeX 0.99995+ comes with xdvipdfmx 20160307+.
+    % It can handle Unicode destination names for PDF.
     \txiuseunicodedestnametrue
   \else
-    % XeTeX < 0.99996 (TeX Live < 2016) cannot be used
+    % XeTeX < 0.99996 (TeX Live < 2016) cannot use the
     % `dvipdfmx:config' special.
     % So for avoiding PDF destination name replacement,
-    % xdvipdfmx commandline option `-C 0x0010' is necessary.
+    % xdvipdfmx's command line option `-C 0x0010' is necessary.
     %
-    % XeTeX < 0.99995 can not handle Unicode destination name for PDF
-    % because xdvipdfmx 20150315 has UTF-16 convert issue.
-    % It fixed by xdvipdfmx 20160106 (TeX Live SVN r39753).
+    % XeTeX < 0.99995 can not handle Unicode destination names for PDF
+    % because xdvipdfmx 20150315 has a UTF-16 conversion issue.
+    % It is fixed by xdvipdfmx 20160106 (TeX Live SVN r39753).
     \txiuseunicodedestnamefalse
   \fi
   %
   % PDF outline support
   %
-  % Emulate the primitive of pdfTeX
+  % Emulate pdfTeX primitive
   \def\pdfdest name#1 xyz{%
     \special{pdf:dest (name#1) address@hidden /XYZ @xpos @ypos null]}%
   }
@@ -1575,7 +1575,7 @@
     \iftxiuseunicodedestname
       \def\pdfdestname{#1}% Pass through Unicode characters.
     \else
-      \edef\pdfdestname{#1}% Replace Unicode characters to ASCII.
+      \edef\pdfdestname{#1}% Replace Unicode characters with ASCII.
     \fi
     \turnoffactive
     \makevalueexpandable
@@ -1587,7 +1587,7 @@
     \iftxiuseunicodedestname
       \def\pdfoutlinedest{#3}% Pass through Unicode characters.
     \else
-      \edef\pdfoutlinedest{#3}% Replace Unicode characters to ASCII.
+      \edef\pdfoutlinedest{#3}% Replace Unicode characters with ASCII.
     \fi
     \ifx\pdfoutlinedest\empty
       \def\pdfoutlinedest{#4}%
@@ -1606,10 +1606,10 @@
   \def\pdfmakeoutlines{%
     \begingroup
       %
-      % In the case of XeTeX, counts of subentries is not necesary.
-      % Therefore, read toc only once.
+      % For XeTeX, counts of subentries are not necessary.
+      % Therefore, we read toc only once.
       %
-      % We use the node names as the destinations.
+      % We use node names as destinations.
       \def\partentry##1##2##3##4{}% ignore parts in the outlines
       \def\numchapentry##1##2##3##4{%
         \dopdfoutline{##1}{1}{##3}{##4}}%
@@ -1629,7 +1629,7 @@
       \let\unnsubsecentry\numsubsecentry%
       \let\unnsubsubsecentry\numsubsubsecentry%
       %
-      % In the case of XeTeX, xdvipdfmx converts strings to UTF-16.
+      % For XeTeX, xdvipdfmx converts strings to UTF-16.
       % Therefore, the encoding and the language may not be considered.
       %
       \indexnofonts
@@ -1651,9 +1651,9 @@
   \special{pdf:docview << /PageMode /UseOutlines >> }
   % ``\special{pdf:tounicode ...}'' is not necessary
   % because xdvipdfmx converts strings from UTF-8 to UTF-16 without it.
-  % However, due to UTF-16 convert issue of xdvipdfmx 20150315,
-  % ``\special{pdf:dest ...}'' can not handle non-ASCII strings.
-  % It fixed by xdvipdfmx 20160106 (TeX Live SVN r39753).
+  % However, due to a UTF-16 conversion issue of xdvipdfmx 20150315,
+  % ``\special{pdf:dest ...}'' cannot handle non-ASCII strings.
+  % It is fixed by xdvipdfmx 20160106 (TeX Live SVN r39753).
 %
   \def\skipspaces#1{\def\PP{#1}\def\D{|}%
     \ifx\PP\D\let\nextsp\relax
@@ -1725,7 +1725,7 @@
     \def\xeteximagewidth{#2}\setbox0 = \hbox{\ignorespaces #2}%
     \def\xeteximageheight{#3}\setbox2 = \hbox{\ignorespaces #3}%
     %
-    % XeTeX (and the PDF format) support .pdf, .png, .jpg (among
+    % XeTeX (and the PDF format) supports .pdf, .png, .jpg (among
     % others).  Let's try in that order, PDF first since if
     % someone has a scalable image, presumably better to use that than a
     % bitmap.
@@ -8857,7 +8857,7 @@
        \iftxiuseunicodedestname
          \def\pdfxrefdest{#1}% Pass through Unicode characters.
        \else
-         \edef\pdfxrefdest{#1}% Replace Unicode characters to ASCII.
+         \edef\pdfxrefdest{#1}% Replace Unicode characters with ASCII.
        \fi
        \ifx\pdfxrefdest\empty
          \def\pdfxrefdest{Top}% no empty targets
@@ -8867,14 +8867,14 @@
        %
        \leavevmode
        \ifnum\filenamelength>0
-         % By the default settings,
+         % With default settings,
          % XeTeX (xdvipdfmx) replaces link destination names with integers.
          % In this case, the replaced destination names of
-         % remote PDF cannot be known. In order to avoid replacement,
-         % you can use commandline option `-C 0x0010' for xdvipdfmx.
+         % remote PDFs are no longer known.  In order to avoid a replacement,
+         % you can use xdvipdfmx's command line option `-C 0x0010'.
          % If you use XeTeX 0.99996+ (TeX Live 2016+),
-         % the commandline option is not neccesary
-         % because we can use `dvipdfmx:config' special.
+         % this command line option is no longer necessary
+         % because we can use the `dvipdfmx:config' special.
          \special{pdf:bann << /Border [0 0 0] /Type /Annot /Subtype /Link /A
            << /S /GoToR /F (\the\filename.pdf) /D (name\pdfxrefdest) >> >>}%
        \else
@@ -9786,9 +9786,9 @@
   \global\righthyphenmin = #3\relax
 }
 
-% XeTeX and LuaTeX can handle native Unicode.
-% Their default I/O is UTF-8 sequence instead of byte-wise.
-% Other TeX engine (pdfTeX etc.) I/O is byte-wise.
+% XeTeX and LuaTeX can handle Unicode natively.
+% Their default I/O uses UTF-8 sequences instead of a byte-wise operation.
+% Other TeX engines' I/O (pdfTeX, etc.) is byte-wise.
 %
 \newif\iftxinativeunicodecapable
 \newif\iftxiusebytewiseio
@@ -9912,14 +9912,15 @@
   %
   \else \ifx \declaredencoding \utfeight
      \iftxinativeunicodecapable
-       % For native Unicode (XeTeX and LuaTeX)
+       % For native Unicode handling (XeTeX and LuaTeX)
        \nativeunicodechardefs
      \else
-       % For UTF-8 byte sequence (TeX, eTeX and pdfTeX)
+       % For treating UTF-8 as byte sequences (TeX, eTeX and pdfTeX)
        \setnonasciicharscatcode\active
        % since we already invoked \utfeightchardefs at the top level
-       % (below), do not re-invoke it, then our check for duplicated
-       % definitions triggers.  Making non-ascii chars active is enough.
+       % (below), do not re-invoke it, otherwise our check for duplicated
+       % definitions gets triggered.  Making non-ascii chars active is
+       % sufficient.
      \fi
   %
   \else
@@ -10267,8 +10268,9 @@
 \def\U#1{%
   \expandafter\ifx\csname uni:#1\endcsname \relax
     \iftxinativeunicodecapable
-      % Any Unicode characters can be used by native Unicode.
-      % However, if the font does not have the glyph, the letter will miss.
+      % All Unicode characters can be used if native Unicode handling is
+      % active.  However, if the font does not have the glyph,
+      % letters are missing.
       \begingroup
         \uccode`\.="#1\relax
         \uppercase{.}
@@ -10291,9 +10293,9 @@
 \def\UTFviiiFourOctetsName#1#2#3#4{%
   \csname u8:#1\string #2\string #3\string #4\endcsname}%
 
-% For UTF-8 byte sequence (TeX, e-TeX and pdfTeX)
-% Definition macro to replace the Unicode character
-% Definition macro that is used by @U command
+% For UTF-8 byte sequences (TeX, e-TeX and pdfTeX),
+% provide a definition macro to replace a Unicode character;
+% this gets used by the @U command
 %
 \begingroup
   \catcode`\"=12
@@ -10381,8 +10383,8 @@
     \uppercase{\gdef\UTFviiiTmp{#2#3#4}}}
 \endgroup
 
-% For native Unicode (XeTeX and LuaTeX)
-% Definition macro that is set catcode other non global
+% For native Unicode handling (XeTeX and LuaTeX),
+% provide a definition macro that sets a catcode to `other' non-globally
 %
 \def\DeclareUnicodeCharacterNativeOther#1#2{%
   \catcode"#1=\other
@@ -11088,8 +11090,8 @@
 \newif\ifpassthroughchars
 \passthroughcharsfalse
 
-% For native Unicode (XeTeX and LuaTeX)
-% Definition macro to replace / pass-through the Unicode character
+% For native Unicode handling (XeTeX and LuaTeX),
+% provide a definition macro to replace/pass-through a Unicode character
 %
 \def\DeclareUnicodeCharacterNative#1#2{%
   \catcode"#1=\active
@@ -11112,21 +11114,22 @@
   \endgroup
 }
 
-% Native Unicode (XeTeX and LuaTeX) character replacing definitions
-% It makes the setting that replace the Unicode characters.
+% Native Unicode handling (XeTeX and LuaTeX) character replacing definition.
+% It activates the setting that replaces Unicode characters.
 \def\nativeunicodechardefs{%
   \let\DeclareUnicodeCharacter\DeclareUnicodeCharacterNative
   \unicodechardefs
 }
 
-% For native Unicode (XeTeX and LuaTeX).  Make the character token expand
+% For native Unicode handling (XeTeX and LuaTeX),
+% make the character token expand
 % to the sequences given in \unicodechardefs for printing.
 \def\DeclareUnicodeCharacterNativeAtU#1#2{%
   \def\UTFAtUTmp{#2}
   \expandafter\globallet\csname uni:#1\endcsname \UTFAtUTmp
 }
 
-% Native Unicode (XeTeX and LuaTeX) @U command definitions
+% @U command definitions for native Unicode handling (XeTeX and LuaTeX).
 \def\nativeunicodechardefsatu{%
   \let\DeclareUnicodeCharacter\DeclareUnicodeCharacterNativeAtU
   \unicodechardefs
@@ -11137,7 +11140,7 @@
    \relax
 }
 
-% define all the unicode characters we know about, for the sake of @U.
+% define all Unicode characters we know about, for the sake of @U.
 \iftxinativeunicodecapable
   \nativeunicodechardefsatu
 \else