gnu: Add julia-datavalueinterfaces.

* gnu/packages/julia-xyz.scm (julia-datavalueinterfaces-1.0.0): New variable.

gnu/packages/julia-xyz.scm

@@ -492,3 +492,24 @@ stubs and very little else.")
     (description "This package provides the type DataValue that is used to
 represent missing data.")
     (license license:expat)))
+
+(define-public julia-datavalueinterfaces
+  (package
+    (name "julia-datavalueinterfaces")
+    (version "1.0.0")
+    (source
+     (origin
+       (method git-fetch)
+       (uri (git-reference
+             (url "https://github.com/queryverse/DataValueInterfaces.jl")
+             (commit (string-append "v" version))))
+       (file-name "DataValueInterfaces")
+       (sha256
+        (base32 "0g2wj6q7jj956nx6g7dk8x7w1c4l2xcmnr1kq5x8s8fild9kslg8"))))
+    (build-system julia-build-system)
+    (home-page "https://github.com/queryverse/DataValueInterfaces.jl")
+    (synopsis "Forward definitions for @code{Datavalues.jl}")
+    (description "This package allows a few forward definitions for the
+@code{DataValues.jl} package that other packages can utilize for integration
+without having to take direct dependencies.")
+    (license license:expat)))