Index: uspace/lib/cpp/include/impl/string.hpp
===================================================================
--- uspace/lib/cpp/include/impl/string.hpp	(revision b1b500b8bce6f1c90be020d1db31b7aeedc953d7)
+++ uspace/lib/cpp/include/impl/string.hpp	(revision 27473fb8071b4c6bee9ba6ac9f3ca3a8be8ba4e0)
@@ -933,5 +933,12 @@
             }
 
-            size_type copy(value_type* str, size_type n, size_type pos = 0) const;
+            size_type copy(value_type* str, size_type n, size_type pos = 0) const
+            {
+                auto len = min(n , size_ - pos);
+                for (size_type i = 0; i < len; ++i)
+                    traits_type::assign(str[i], data_[pos + i]);
+
+                return len;
+            }
 
             void swap(basic_string& other)