The cause of the issue was a clash about ``\titleref`` macro being already
defined in memoir class context. To avoid similar problems, this makes
the text styling macros
``\strong``, ``\code``, ``\bfcode``, ``\email``, ``\tablecontinued``,
``\titleref``, ``\menuselection``, ``\accelerator``, ``\crossref``,
``\termref``, ``\optional``,
also available with ``\sphinx`` prefix, with a conf.py boolean option to
let sphinx.sty only define ``\sphinx``-prefixed macros. As default value
is False, backwards compatibility is maintained.
On this occasion, some internal non-public macros have been renamed with
prefix ``\spx@``. The command
find . -name '*.sty' -exec grep -l \\\\spx@ {} \;
has been executed in TeXLive 2015 and 2016 installations to check no
package defines macros starting with ``\spx@``.
Some internal macros having public names (because they are written by
latex.py into the body of the latex document) have been renamed to have
``\sphinx`` prefix. The macros in sphinx.sty starting with \py@, or \DU,
or \PYG have not been modified. Similarly ``\release``, ``\version``,
``\releasename``, etc... have not been renamed.
`html_last_updated_fmt` is commonly used for non date formatting. But
LDML is difficult to represent them from its characteristics.
Now we moved to strftime format again (ref: #2394).
In 423bf7b, I tried to add fallback mechanism to ``python3``. But it breaks
the python3 highlighting on python2 environment.
This adds ``'default'`` to highlighting languages; it works like
``'python3'``, but fallbacks if failed Highlighting. And this removes
try-parse step from ``'python3'`` language. Now, it highlights regardless of
runtime environments. Thanks to Yoshiki SHIBUKAWA.
References: #2279.
This means that source code is highlighted as Python 3 (which is mostly
a superset of Python 2), and no parsing is attempted to distinguish
valid code.
This is useful because if you run linkcheck often, you are likely to see lots of transient network errors, which usually disappear if you simply try again.
