diff --git a/example/array.usage.cpp b/example/array.usage.cpp
index 8c93dc7..cf82625 100644
--- a/example/array.usage.cpp
+++ b/example/array.usage.cpp
@@ -4,7 +4,7 @@
 using namespace std;
 
 int main() {
-  Array a (10);
+  Array<int> a (10);
 
   for (int i = 0; i < 1000; ++i) a[i] = i;
 
diff --git a/lib/array.h b/lib/array.h
index 465e931..528c0ba 100644
--- a/lib/array.h
+++ b/lib/array.h
@@ -61,7 +61,7 @@ class Array {
     return slice[index_in_slice];
   };
 
-  
+
 public:
   int length;
 
@@ -136,6 +136,22 @@ class Array {
   };
 
 
+  // Check, whether all of elements
+  // in array satisfy requirement
+  //   fn - function, which returns
+  //        true or false
+  //
+  bool every(bool (*fn)(T)) {
+    for (int i = 0; i < this->length; ++i) {
+      T item = this->get(i);
+      bool satisfies = fn(item);
+      if (!satisfies) return 0;
+    }
+
+    return 1;
+  };
+
+
   // Create string from elements of array
   // separated by specified separator
   //