Revert "core/formats: implement ToString instead of Display for NAChannelType"

This reverts commit 81b94329a275bb92066404bd3bb2822c5bb3f424.

I forgot that implemented Display means automatic ToString() and not vice versa.

1 files changed, 5 insertions, 4 deletions

diff --git a/nihav-core/src/formats.rs b/nihav-core/src/formats.rs
index 6d7f1a1..f96eb53 100644
--- a/nihav-core/src/formats.rs
+++ b/nihav-core/src/formats.rs
@@ -216,9 +216,9 @@ impl FromStr for NAChannelType {
     }
 }
 
-impl ToString for NAChannelType {
-    fn to_string(&self) -> String {
-        match *self {
+impl fmt::Display for NAChannelType {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        let name = match *self {
             NAChannelType::C    => "C".to_string(),
             NAChannelType::L    => "L".to_string(),
             NAChannelType::R    => "R".to_string(),
@@ -247,7 +247,8 @@ impl ToString for NAChannelType {
             NAChannelType::Rt   => "Rt".to_string(),
             NAChannelType::Lo   => "Lo".to_string(),
             NAChannelType::Ro   => "Ro".to_string(),
-        }
+        };
+        write!(f, "{}", name)
     }
 }