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New function ‘icuGetCollate()’ to report on the ICU collation locale in use (if any).
‘capabilities()’ now reports if ICU is compiled in for use for collation (it is only actually used if a suitable locale is set for collation, and never for a ‘C’ locale).
(OS X only.) Package ‘tcltk’ checks when loaded if it is linked against the CRAN X11-based Tcl/Tk and if so that the Tcl/Tk component and the X11 libraries are installed. This allows more informative error messages to be given.
The ‘X11()’ device and X11-based versions of the data editor and viewer (invoked by ‘edit()’ and ‘View()’ for data frames and matrices from command-line R) check that the X11 libraries are installed.