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diff --git a/libbutl/small-forward-list.hxx b/libbutl/small-forward-list.hxx
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+++ b/libbutl/small-forward-list.hxx
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+// file      : libbutl/small-forward-list.hxx -*- C++ -*-
+// license   : MIT; see accompanying LICENSE file
+
+#pragma once
+
+#include <cstddef>      // size_t
+#include <utility>      // move()
+#include <type_traits>  // is_nothrow_move_constructible
+#include <forward_list>
+
+#include <libbutl/small-allocator.hxx>
+
+#include <libbutl/export.hxx>
+
+namespace butl
+{
+  // Issues and limitations.
+  //
+  // - Because small_allocator currently expects us to allocate the entire
+  //   small buffer and there is no reserve() in std::forward_list, we
+  //   currently only support N==1 (which we static_assert).
+  //
+  // - swap() is deleted (see notes below).
+  //
+  // - The implementation doesn't allocate T but rather a "node" that normally
+  //   consists of a pointers (next) and T.
+  //
+  template <typename T>
+  using small_forward_list_node =
+#if   defined (_MSC_VER)
+  std::_Flist_node<T, void*>;
+#elif defined (__GLIBCXX__)
+  std::_Fwd_list_node<T>;
+#elif defined (_LIBCPP_VERSION)
+  std::__forward_list_node<T, void*>;
+#else
+#error unknown standard library implementation
+#endif
+
+  template <typename T, std::size_t N>
+  using small_forward_list_buffer =
+    small_allocator_buffer<small_forward_list_node<T>, N>;
+
+  template <typename T, std::size_t N>
+  class small_forward_list:
+    private small_forward_list_buffer<T, N>,
+    public std::forward_list<T,
+                             small_allocator<T,
+                                             N,
+                                             small_forward_list_buffer<T, N>>>
+  {
+    static_assert (N == 1, "only small_forward_list or 1 currently supported");
+
+  public:
+    static constexpr const std::size_t small_size = N;
+
+    using buffer_type = small_forward_list_buffer<T, N>;
+    using allocator_type = small_allocator<T, N, buffer_type>;
+    using base_type = std::forward_list<T, allocator_type>;
+
+    small_forward_list ()
+      : base_type (allocator_type (this)) {}
+
+    small_forward_list (std::initializer_list<T> v)
+      : base_type (allocator_type (this))
+    {
+      static_cast<base_type&> (*this) = v;
+    }
+
+    template <typename I>
+    small_forward_list (I b, I e)
+      : base_type (allocator_type (this))
+    {
+      this->assign (b, e);
+    }
+
+    explicit
+    small_forward_list (std::size_t n)
+      : base_type (allocator_type (this))
+    {
+      this->resize (n);
+    }
+
+    small_forward_list (std::size_t n, const T& x)
+      : base_type (allocator_type (this))
+    {
+      this->assign (n, x);
+    }
+
+    small_forward_list (const small_forward_list& v)
+      : buffer_type (), base_type (allocator_type (this))
+    {
+      static_cast<base_type&> (*this) = v;
+    }
+
+    small_forward_list&
+    operator= (const small_forward_list& v)
+    {
+      // Note: propagate_on_container_copy_assignment = false
+      //
+      static_cast<base_type&> (*this) = v;
+      return *this;
+    }
+
+    // See small_vector for the move-constructor/assignment noexept
+    // expressions reasoning.
+    //
+    small_forward_list (small_forward_list&& v)
+#if !defined(_MSC_VER) || _MSC_VER > 1900
+      noexcept (std::is_nothrow_move_constructible<T>::value)
+#endif
+      : base_type (allocator_type (this))
+    {
+      *this = std::move (v); // Delegate to operator=(&&).
+    }
+
+    small_forward_list&
+    operator= (small_forward_list&& v) noexcept (false)
+    {
+      // VC14's implementation of operator=(&&) swaps pointers without regard
+      // for allocator (fixed in 15).
+      //
+#if defined(_MSC_VER) && _MSC_VER <= 1900
+      clear ();
+      for (T& x: v)
+        push_front (std::move (x));
+      reverse ();
+      v.clear ();
+#else
+      // Note: propagate_on_container_move_assignment = false
+      //
+      static_cast<base_type&> (*this) = std::move (v);
+#endif
+
+      return *this;
+    }
+
+    small_forward_list&
+    operator= (std::initializer_list<T> v)
+    {
+      static_cast<base_type&> (*this) = v;
+      return *this;
+    }
+
+    // Implementing swap() under small buffer optimization is not trivial, to
+    // say the least (think of swapping two such buffers of different sizes).
+    // One easy option would be to force both in to the heap.
+    //
+    void
+    swap (small_forward_list&) = delete;
+  };
+}