07/20: gnu: Add rust-downcast-rs-1.1.

[guix-commits]

efraim pushed a commit to branch master
in repository guix.

commit 959b93a66032c4f647d0e1209b855e7762dbd10b
Author: Valentin Ignatev <address@hidden>
AuthorDate: Wed Jan 15 04:10:19 2020 +0300

    gnu: Add rust-downcast-rs-1.1.
    
    * gnu/packages/crates-io.scm (rust-downcast-rs-1.1): New variable.
    
    Signed-off-by: Efraim Flashner <address@hidden>
---
 gnu/packages/crates-io.scm | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/gnu/packages/crates-io.scm b/gnu/packages/crates-io.scm
index 1db1b61..3391533 100644
--- a/gnu/packages/crates-io.scm
+++ b/gnu/packages/crates-io.scm
@@ -2996,6 +2996,27 @@ from macros.")
     (description "Command line argument parsing.")
     (license (list license:expat license:unlicense))))
 
+(define-public rust-downcast-rs-1.1
+  (package
+    (name "rust-downcast-rs")
+    (version "1.1.1")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (crate-uri "downcast-rs" version))
+       (file-name
+        (string-append name "-" version ".tar.gz"))
+       (sha256
+        (base32
+         "1xhs2qj02k9m4mm5fgh19y88850y9jsnwwlblf2ffc91gjs6xfjj"))))
+    (build-system cargo-build-system)
+    (home-page "https://github.com/marcianx/downcast-rs";)
+    (synopsis "Trait object downcasting support using only safe Rust")
+    (description
+     "Trait object downcasting support using only safe Rust.  It supports type
+parameters, associated types, and type constraints.")
+    (license (list license:expat license:asl2.0))))
+
 (define-public rust-dtoa-0.4
   (package
     (name "rust-dtoa")