supported: it no longer falls back to C++98.

PCRE2 is used if available.  To make use of PCRE1 if PCRE2

can be rebuilt from the tarball created by

the source files are properly cleaned by

instructing the tester to do so.  This can be temporarily

circumvented during development by setting environment variable

There is the beginnings of support for the recently approved

C++20 standard, specified analogously to C++14 and C++17.  There is

currently only limited support for this in compilers, with flags

is deprecated now.  Such use has been rare, and has

as expected in some cases only.  In other cases, wrong

silently been truncated, not detecting previous errors.

Long-standing issue where the X11 device could lose events

shortly after startup has been addressed (

to work more consistently, thanks to suggestions by

calls with named arguments where needed.

the title string contains a character which would produce corrupt

also work for 0-length data frames, after reports by

Primitive replacement functions no longer mutate a

referenced first argument when used outside of a complex

(for now) been replaced with much faster

consistently and have the same non-explicit default (

Wang Jiefei for analyzing this; similar change has been made in

Especially for binary observations with high or low fitted

probabilities, this effectively deleted all observations of 1 or

0.  Also, the type of residuals used in the

in general have approximately zero mean.

, Cook's distance was computed from unweighted

residuals, leading to inconsistencies.  Replaced with usual weighted

Johann Kleinbub and analysis and patch by

argument which should fix behaviour during

; thanks to a careful algorithm originally

prompted by the report from Adam Wheeler and then others, in

is much more rational now, notably for large

Inheritance information on S4 classes is maintained more

consistently, particularly in the case of class unions (in part

The warning message when attempting to export an nonexistent

misbehaved in corner cases where it switched

combining use of box constraints and fixed starting values (in