diff --git a/src/format.rs b/src/format.rs
index b9e6f04..4131c2b 100644
--- a/src/format.rs
+++ b/src/format.rs
@@ -205,7 +205,6 @@ impl Pattern {
 }
 
 /// Ensure that the indentation returns to zero at the end of the file
-fn indents_return_to_zero(state: &State) -> bool {
-    #![allow(clippy::missing_const_for_fn)]
+const fn indents_return_to_zero(state: &State) -> bool {
     state.indent.actual == 0
 }
diff --git a/src/indent.rs b/src/indent.rs
index 608bf86..ac531c8 100644
--- a/src/indent.rs
+++ b/src/indent.rs
@@ -55,10 +55,10 @@ fn get_diff(line: &str, pattern: &Pattern) -> i8 {
     };
 
     // indent for delimiters
-    diff += i8::try_from(line.chars().filter(|x| OPENS.contains(x)).count())
-        .unwrap();
-    diff -= i8::try_from(line.chars().filter(|x| CLOSES.contains(x)).count())
-        .unwrap();
+    diff += line
+        .chars()
+        .map(|x| i8::from(OPENS.contains(&x)) - i8::from(CLOSES.contains(&x)))
+        .sum::<i8>();
 
     diff
 }