Improve type names

day_07/src/equation/operator_set.rs

@@ -1,4 +1,6 @@
+use std::collections::HashMap;
 use std::collections::HashSet;
+use std::sync::{Arc, LazyLock, Mutex};
 
 #[derive(Debug, Clone, Copy, Hash, PartialEq, Eq)]
 pub enum Op {
@@ -19,19 +21,18 @@ impl PermutationCacheKey {
     }
 }
 
-use std::collections::HashMap;
-use std::sync::{LazyLock, Mutex};
+type Permutation = Vec<Op>;
 
-type OperatorCache = HashMap<PermutationCacheKey, HashSet<Vec<Op>>>;
+type OperatorCache = HashMap<PermutationCacheKey, HashSet<Permutation>>;
 
 static OPERATOR_SET_CACHE: LazyLock<Mutex<OperatorCache>> =
     LazyLock::new(|| Mutex::new(HashMap::new()));
 
-fn check_operator_set_cache(cache_key: &PermutationCacheKey) -> Option<HashSet<Vec<Op>>> {
+fn check_operator_set_cache(cache_key: &PermutationCacheKey) -> Option<HashSet<Permutation>> {
     OPERATOR_SET_CACHE.lock().unwrap().get(cache_key).cloned()
 }
 
-fn store_operator_set_in_cache(cache_key: PermutationCacheKey, cache_value: HashSet<Vec<Op>>) {
+fn store_operator_set_in_cache(cache_key: PermutationCacheKey, cache_value: HashSet<Permutation>) {
     OPERATOR_SET_CACHE
         .lock()
         .unwrap()
@@ -41,8 +42,8 @@ fn store_operator_set_in_cache(cache_key: PermutationCacheKey, cache_value: Hash
 fn create_permutations_recurse(
     values: &[Op],
     len: usize,
-    permutations: &mut HashSet<Vec<Op>>,
-    curr_permutation: Vec<Op>,
+    permutations: &mut HashSet<Permutation>,
+    curr_permutation: Permutation,
 ) {
     if curr_permutation.len() == len {
         permutations.insert(curr_permutation);
@@ -56,7 +57,7 @@ fn create_permutations_recurse(
     }
 }
 
-pub fn create_permutations(set: &[Op], len: usize) -> HashSet<Vec<Op>> {
+pub fn create_permutations(set: &[Op], len: usize) -> HashSet<Permutation> {
     let cache_key = PermutationCacheKey::new(len, set.to_vec());
     if let Some(cached_value) = check_operator_set_cache(&cache_key) {
         return cached_value;