gnu: Add r-xmisc.

* gnu/packages/cran.scm (r-xmisc): New variable.

gnu/packages/cran.scm

@@ -19315,3 +19315,25 @@ Raftery, Appl.Statistics, 1989); it includes inference and basic methods.")
 univariate time series forecasts including exponential smoothing via state
 space models and automatic ARIMA modelling.")
     (license license:gpl3)))
+
+(define-public r-xmisc
+  (package
+    (name "r-xmisc")
+    (version "0.2.1")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (cran-uri "Xmisc" version))
+       (sha256
+        (base32
+         "11gwlcyxhz1p50m68cnqrxmisdk99v8vrsbvyr7k67f0kvsznzs1"))))
+    (properties `((upstream-name . "Xmisc")))
+    (build-system r-build-system)
+    (home-page "https://cran.r-project.org/package=Xmisc")
+    (synopsis
+     "Xiaobei's miscellaneous classes and functions")
+    (description
+     "This package provides Xiaobei's miscellaneous classes and functions,
+which are useful when developing R packages for @dfn{object oriented
+programming} (OOP) using R Reference Class.")
+    (license license:gpl2+)))