based on the TRE library of Ville Laurikari, a modified copy of

This is often faster, especially in a MBCS locale.

Some known differences are that it is less tolerant of invalid

inputs in MBCS locales, and in its interpretation of undefined

in caseless matching is no longer to map

as warned about in the help page does not work

in this engine (it did in the previous one since 2005).

Extended (and basic) regexps now support same set of options

and support for UTF-8-encoded strings in

now has full support for MBCS locales with a modest

matching character-wise rather than byte-wise.

matching twice and so is usually faster.

non-UTF-8 MBCS locale, by translating the inputs to UTF-8.

now inhibits the translation of inputs with

(as multiple compilation of regexps is avoided).

and should be consulted for details of the new implementations.

A new dynamic HTML help system is used by default, and may be

HTML help pages will be generated on request, resolving links

(it used to on Unix but not on Windows).  Nor does it on

http server will update the package index at first use.

default set by the option of that name) to supersede arguments

in the workspace or further down the search path, otherwise

Plain text help is now used as the fallback for HTML help (as

it always was for Compiled HTML help on Windows).

It is possible to ask for static HTML pages to be prebuilt

may be useful for those who wish to make HTML help available

files, to evaluate expressions at build, install, or render time.

Currently install time and render time evaluation are supported.

added to allow format-specific (or more general, using

parser has been made more tolerant of coding

errors in Rd files:  now all syntax errors are reported as

warnings, and an attempt is made to continue parsing.

) to accept small fragments of Rd files (so

can output Rd code which is then parsed).

rendering functions have a new argument,

no longer includes the newline as part of

There have been various bug fixes and code reorganization in

All example files are now created with either ASCII or UTF-8