remove needless pass by value

2 files changed, 4 insertions, 4 deletions

diff --git a/src/de.rs b/src/de.rs
index 44f324d..2d5722d 100644
--- a/src/de.rs
+++ b/src/de.rs
@@ -232,7 +232,7 @@ impl<'de> de::MapAccess<'de> for MapAccess {
         V: de::DeserializeSeed<'de>,
     {
         let (key, value) = self.elements.pop_front().unwrap();
-        de::DeserializeSeed::deserialize(seed, value).map_err(|e| e.prepend_key(key))
+        de::DeserializeSeed::deserialize(seed, value).map_err(|e| e.prepend_key(&key))
     }
 }
 
diff --git a/src/error.rs b/src/error.rs
index 83ee416..46dc47f 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -134,7 +134,7 @@ impl ConfigError {
     }
 
     #[must_use]
-    fn prepend(self, segment: String, add_dot: bool) -> Self {
+    fn prepend(self, segment: &str, add_dot: bool) -> Self {
         let concat = |key: Option<String>| {
             let key = key.unwrap_or_else(String::new);
             let dot = if add_dot && key.as_bytes().get(0).unwrap_or(&b'[') != &b'[' {
@@ -162,13 +162,13 @@ impl ConfigError {
     }
 
     #[must_use]
-    pub(crate) fn prepend_key(self, key: String) -> Self {
+    pub(crate) fn prepend_key(self, key: &str) -> Self {
         self.prepend(key, true)
     }
 
     #[must_use]
     pub(crate) fn prepend_index(self, idx: usize) -> Self {
-        self.prepend(format!("[{}]", idx), false)
+        self.prepend(&format!("[{}]", idx), false)
     }
 }