# System.Collections.Frozen

``` diff
 namespace System.Collections.Frozen {
     public static class FrozenDictionary {
-        public static FrozenDictionary<TKey, TValue> ToFrozenDictionary<TKey, TValue>(this IEnumerable<KeyValuePair<TKey, TValue>> source, bool optimizeForReading);

-        public static FrozenDictionary<TKey, TValue> ToFrozenDictionary<TKey, TValue>(this IEnumerable<KeyValuePair<TKey, TValue>> source, IEqualityComparer<TKey>? comparer, bool optimizeForReading);

     }
     public static class FrozenSet {
-        public static FrozenSet<T> ToFrozenSet<T>(this IEnumerable<T> source, bool optimizeForReading);

-        public static FrozenSet<T> ToFrozenSet<T>(this IEnumerable<T> source, IEqualityComparer<T>? comparer, bool optimizeForReading);

     }
 }
```

