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+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __FN_MULTI_FUNCTION_CONTEXT_HH__
+#define __FN_MULTI_FUNCTION_CONTEXT_HH__
+
+/** \file
+ * \ingroup fn
+ *
+ * An #MFContext is passed along with every call to a multi-function. Right now it does nothing,
+ * but it can be used for the following purposes:
+ * - Pass debug information up and down the function call stack.
+ * - Pass reusable memory buffers to sub-functions to increase performance.
+ * - Pass cached data to called functions.
+ */
+
+#include "BLI_utildefines.h"
+
+#include "BLI_map.hh"
+
+namespace blender::fn {
+
+class MFContext;
+
+class MFContextBuilder {
+ private:
+  Map<std::string, const void *> global_contexts_;
+
+  friend MFContext;
+
+ public:
+  template<typename T> void add_global_context(std::string name, const T *context)
+  {
+    global_contexts_.add_new(std::move(name), (const void *)context);
+  }
+};
+
+class MFContext {
+ private:
+  MFContextBuilder &builder_;
+
+ public:
+  MFContext(MFContextBuilder &builder) : builder_(builder)
+  {
+  }
+
+  template<typename T> const T *get_global_context(StringRef name) const
+  {
+    const void *context = builder_.global_contexts_.lookup_default_as(name, nullptr);
+    /* TODO: Implement type checking. */
+    return (const T *)context;
+  }
+};
+
+}  // namespace blender::fn
+
+#endif /* __FN_MULTI_FUNCTION_CONTEXT_HH__ */