gnu: Add emacs-poly-r.

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

gnu/packages/statistics.scm

@@ -36,6 +36,7 @@
   #:use-module (guix git-download)
   #:use-module (guix utils)
   #:use-module (guix build-system ant)
+  #:use-module (guix build-system emacs)
   #:use-module (guix build-system gnu)
   #:use-module (guix build-system r)
   #:use-module (guix build-system python)
@@ -5927,6 +5928,33 @@ is designed to support editing of scripts and interaction with various
 statistical analysis programs such as R, Julia, and JAGS.")
       (license license:gpl3+))))
 
+(define-public emacs-poly-r
+  (package
+    (name "emacs-poly-r")
+    (version "0.2.2")
+    (source
+     (origin
+       (method git-fetch)
+       (uri (git-reference
+             (url "https://github.com/polymode/poly-R")
+             (commit (string-append "v" version))))
+       (file-name (git-file-name name version))
+       (sha256
+        (base32 "0a4wx73jkngw5nbq1fa4jfhba6bsmyn6vnsf887x3xhb5v3ykhsg"))))
+    (build-system emacs-build-system)
+    (propagated-inputs
+     `(("emacs-ess" ,emacs-ess)
+       ("emacs-poly-noweb" ,emacs-poly-noweb)
+       ("emacs-polymode-markdown" ,emacs-polymode-markdown)
+       ("emacs-polymode" ,emacs-polymode)))
+    (properties '((upstream-name . "poly-R")))
+    (home-page "https://github.com/polymode/poly-markdown")
+    (synopsis "Polymodes for the R language")
+    (description
+     "This package provides a number of polymodes for working with mixed R
+files, including Rmarkdown files.")
+    (license license:gpl3+)))
+
 (define-public readstat
   (package
     (name "readstat")