Merge pull request #415 from alexmurari/patch-1

Avoid multiple enumeration
vkhorikov · Jun 11, 2022 · 569b3c4 · 569b3c4
2 parents f24e7dc + d2bbca1
commit 569b3c4
Showing 1 changed file with 5 additions and 1 deletion.
diff --git a/CSharpFunctionalExtensions/Maybe/MaybeExtensions.cs b/CSharpFunctionalExtensions/Maybe/MaybeExtensions.cs
@@ -329,6 +329,8 @@ public static IEnumerable<T> Choose<T>(this IEnumerable<Maybe<T>> source)
 
         public static Maybe<T> TryFirst<T>(this IEnumerable<T> source)
         {
+            source = source as ICollection<T> ?? source.ToList();
+
             if (source.Any())
             {
                 return Maybe<T>.From(source.First());
@@ -350,6 +352,8 @@ public static Maybe<T> TryFirst<T>(this IEnumerable<T> source, Func<T, bool> pre
 
         public static Maybe<T> TryLast<T>(this IEnumerable<T> source)
         {
+            source = source as ICollection<T> ?? source.ToList();
+
             if (source.Any())
             {
                 return Maybe<T>.From(source.Last());
@@ -396,4 +400,4 @@ public static void Deconstruct<T>(this Maybe<T> result, out bool hasValue, out T
             value = result.GetValueOrDefault();
         }
     }
-}
+}