gnu: Add rust-unchecked-index-0.2.

* gnu/packages/crates-io.scm (rust-unchecked-index-0.2): New variable.

Signed-off-by: Efraim Flashner <efraim@flashner.co.il>

gnu/packages/crates-io.scm

@@ -7394,6 +7394,27 @@ with the Unicode character database.")
     (license (list license:asl2.0
                    license:expat))))
 
+(define-public rust-unchecked-index-0.2
+  (package
+    (name "rust-unchecked-index")
+    (version "0.2.2")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (crate-uri "unchecked-index" version))
+       (file-name
+        (string-append name "-" version ".tar.gz"))
+       (sha256
+        (base32
+         "0p6qcai1mjayx59cpgk27d0zgw9hz9r1ira5jiqil66f4ba8dfpf"))))
+    (build-system cargo-build-system)
+    (arguments `(#:skip-build? #t))
+    (home-page "https://github.com/bluss/unchecked-index")
+    (synopsis "Unchecked indexing wrapper using regular index syntax")
+    (description
+     "Unchecked indexing wrapper using regular index syntax.")
+    (license (list license:asl2.0 license:expat))))
+
 (define-public rust-unicase-2.4
   (package
     (name "rust-unicase")