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keep the type_name a &'static str

Co-authored-by: Yoshua Wuyts <[email protected]>

Author: jbr

src/error.rs

@@ -16,7 +16,7 @@ pub type Result<T> = std::result::Result<T, Error>;
 pub struct Error {
     error: anyhow::Error,
     status: crate::StatusCode,
-    type_name: Option<String>,
+    type_name: Option<&'static str>,
 }
 
 impl Error {
@@ -36,7 +36,7 @@ impl Error {
                 .try_into()
                 .expect("Could not convert into a valid `StatusCode`"),
             error: error.into(),
-            type_name: Some(std::any::type_name::<E>().to_string()),
+            type_name: Some(std::any::type_name::<E>()),
         }
     }