static template context for errors

src/main.rs

@@ -14,6 +14,7 @@ use rocket_dyn_templates::Template;
 use rand::distributions::Uniform;
 use rand::Rng;
 
+use lazy_static::lazy_static;
 use std::collections::HashMap;
 use std::ops::Deref;
 use std::sync::Arc;
@@ -26,6 +27,10 @@ use std::time::Duration;
 
 const DB_FILENAME: &str = "db.dat";
 
+lazy_static! {
+    static ref EMPTY_MAP: HashMap<String, String> = HashMap::new();
+}
+
 trait ErrorEmpty {
     type Output;
     fn err_empty(self) -> Result<Self::Output, ()>;
@@ -48,12 +53,10 @@ enum WebError {
 
 impl WebError {
     fn not_found() -> Self {
-        let context: HashMap<String, String> = HashMap::new();
-        WebError::NotFound(Template::render("404", context))
+        WebError::NotFound(Template::render("404", EMPTY_MAP.deref()))
     }
     fn server_error() -> Self {
-        let context: HashMap<String, String> = HashMap::new();
-        WebError::ServerError(Template::render("500", context))
+        WebError::ServerError(Template::render("500", EMPTY_MAP.deref()))
     }
 }