gnu: Add rust-rt-format-0.3.

* gnu/packages/crates-io.scm (rust-rt-format-0.3): New variable.

Signed-off-by: Andrew Tropin <andrew@trop.in>

gnu/packages/crates-io.scm

@@ -68276,6 +68276,32 @@ Rust.")
       "High performance inflection transformation library for changing properties of words like the case.")
     (license license:expat)))
 
+(define-public rust-rt-format-0.3
+  (package
+    (name "rust-rt-format")
+    (version "0.3.1")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (crate-uri "rt-format" version))
+       (file-name (string-append name "-" version ".tar.gz"))
+       (sha256
+        (base32 "1qjjwh9ny95xck1kp99gi6hfm9glrx54jx8npnj6yccxc7p7q225"))))
+    (build-system cargo-build-system)
+    (arguments
+     `(#:skip-build? #t
+       #:cargo-inputs
+       (("rust-lazy-static" ,rust-lazy-static-1)
+        ("rust-regex" ,rust-regex-1))))
+    (home-page "https://github.com/vstojkovic/rt-format")
+    (synopsis "Runtime equivalent of the Rust format! macro")
+    (description "This package provides a runtime equivalent of the Rust
+format! macro. It allows formatting strings like the format! macro, with the
+formatting string and the arguments provided at runtime.  This crate supports
+all the formatting features of the format! macro, except for the fill
+character.")
+    (license license:asl2.0)))
+
 (define-public rust-rustc-workspace-hack-1
   (package
     (name "rust-rustc-workspace-hack")