[6207] texi2dvi comments

[Gavin D. Smith]

Revision: 6207
          http://svn.sv.gnu.org/viewvc/?view=rev&root=texinfo&revision=6207
Author:   gavin
Date:     2015-04-07 09:48:14 +0000 (Tue, 07 Apr 2015)
Log Message:
-----------
texi2dvi comments

Modified Paths:
--------------
    trunk/ChangeLog
    trunk/util/texi2dvi

Modified: trunk/ChangeLog
===================================================================
--- trunk/ChangeLog     2015-04-06 23:10:09 UTC (rev 6206)
+++ trunk/ChangeLog     2015-04-07 09:48:14 UTC (rev 6207)
@@ -1,3 +1,7 @@
+2015-04-07  Gavin Smith  <address@hidden>
+
+       * util/texi2dvi: Comments changed.
+
 2015-04-06  Sergey Poznyakoff  <address@hidden>
 
        * util/texi2dvi (comment_iftex, uncomment_iftex): preserve @top

Modified: trunk/util/texi2dvi
===================================================================
--- trunk/util/texi2dvi 2015-04-06 23:10:09 UTC (rev 6206)
+++ trunk/util/texi2dvi 2015-04-07 09:48:14 UTC (rev 6207)
@@ -1569,7 +1569,11 @@
   export $var
 done
 
-# A sed script that preprocesses Texinfo sources in order to keep the
+# Unfortunately, makeinfo --iftex --no-ifinfo doesn't work well enough
+# in versions before 5.0, as makeinfo can't parse the TeX commands
+# inside @tex blocks, so work around with sed.
+#
+# This sed script preprocesses Texinfo sources in order to keep the
 # iftex sections only.  We want to remove non-TeX sections, and comment
 # (with address@hidden _texi2dvi') TeX sections so that makeinfo does not try 
to
 # parse them.  Nevertheless, while commenting TeX sections, don't
@@ -1578,12 +1582,11 @@
 # it being missed.  Comment it out after preprocessing, so that it does
 # not appear in the generated document.
 #
-# Unfortunately makeinfo --iftex --no-ifinfo doesn't work well enough
-# (yet), makeinfo can't parse the TeX commands, so work around with sed.
+# We assume that address@hidden _texi2dvi' or address@hidden (_texi2dvi)' 
starting a line is
+# not present in the document.  Additionally, conditionally defined
+# macros inside the @top node may end up with the wrong value, although
+# this is unlikely in practice.
 #
-# We assume that address@hidden _texi2dvi' starting a line is not present in 
the
-# document.
-#
 comment_iftex=\
 '/address@hidden/,/address@hidden tex/{
   s/^/@c _texi2dvi/
@@ -1610,8 +1613,9 @@
 s/address@hidden/@c address@hidden/
 s/address@hidden ifnotinfo/@c address@hidden ifnotinfo/'
 
-# Uncommenting is simpler: remove any leading address@hidden texi2dvi'; 
repeated
-# copies can sneak in via macro invocations.
+# Uncomment @iftex blocks by removing any leading address@hidden texi2dvi' 
(repeated
+# copies can sneak in via macro invocations).  Likewise, comment out
+# the @top node inside a @ifnottex block.
 uncomment_iftex=\
 's/address@hidden _texi2dvi\(@c _texi2dvi\)*//
 /address@hidden (_texi2dvi)@ifnottex/,/address@hidden (_texi2dvi)@end 
ifnottex/{