fix no_std

src/display.rs

@@ -1,7 +1,7 @@
 #[cfg(not(feature = "std"))]
-use core::fmt::{Display, Formatter};
+use core::fmt::{self, Display, Formatter};
 #[cfg(feature = "std")]
-use std::fmt::{Display, Formatter};
+use std::fmt::{self, Display, Formatter};
 
 use typenum::Integer;
 
@@ -172,7 +172,7 @@ where
     Candela: Integer,
     T: Display + 'static,
 {
-    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         write!(f, "{}", self.value)?;
         // derived units with special symbols
         display_special_unit!(f, Self,

src/lib.rs

@@ -1,3 +1,4 @@
+#![cfg_attr(not(feature = "std"), no_std)]
 mod display;
 pub mod types;