gnu: Add r-purrr.

* gnu/packages/statistics.scm (r-purrr): New variable.

gnu/packages/statistics.scm

@@ -3117,6 +3117,31 @@ and tidyr provides no margins or aggregation.")
 It uses and relies on grid graphics and formal (S4) classes and methods.")
     (license license:gpl2+)))
 
+(define-public r-purrr
+  (package
+    (name "r-purrr")
+    (version "0.2.2")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (cran-uri "purrr" version))
+       (sha256
+        (base32
+         "0lss8q733nv7s154wargm6vnxq55qygnxakib8xdj4jv0y86sxc3"))))
+    (build-system r-build-system)
+    (propagated-inputs
+     `(("r-bh" ,r-bh)
+       ("r-dplyr" ,r-dplyr)
+       ("r-lazyeval" ,r-lazyeval)
+       ("r-magrittr" ,r-magrittr)
+       ("r-rcpp" ,r-rcpp)))
+    (home-page "https://github.com/hadley/purrr")
+    (synopsis "Functional programming tools")
+    (description
+     "This package completes R's functional programming tools with missing
+features present in other programming languages.")
+    (license license:gpl3+)))
+
 (define-public r-plotly
   (package
     (name "r-plotly")