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diff --git a/source/blender/functions/FN_multi_function_signature.hh b/source/blender/functions/FN_multi_function_signature.hh
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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_SIGNATURE_HH__
+#define __FN_MULTI_FUNCTION_SIGNATURE_HH__
+
+/** \file
+ * \ingroup fn
+ *
+ * The signature of a multi-function contains the functions name and expected parameters. New
+ * signatures should be build using the #MFSignatureBuilder class.
+ */
+
+#include "FN_multi_function_param_type.hh"
+
+#include "BLI_vector.hh"
+
+namespace blender::fn {
+
+struct MFSignature {
+  std::string function_name;
+  Vector<std::string> param_names;
+  Vector<MFParamType> param_types;
+  Vector<int> param_data_indices;
+  bool depends_on_context = false;
+
+  int data_index(int param_index) const
+  {
+    return param_data_indices[param_index];
+  }
+};
+
+class MFSignatureBuilder {
+ private:
+  MFSignature &data_;
+  int span_count_ = 0;
+  int virtual_span_count_ = 0;
+  int virtual_array_span_count_ = 0;
+  int vector_array_count_ = 0;
+
+ public:
+  MFSignatureBuilder(MFSignature &data) : data_(data)
+  {
+    BLI_assert(data.param_names.is_empty());
+    BLI_assert(data.param_types.is_empty());
+    BLI_assert(data.param_data_indices.is_empty());
+  }
+
+  /* Input Parameter Types */
+
+  template<typename T> void single_input(StringRef name)
+  {
+    this->single_input(name, CPPType::get<T>());
+  }
+  void single_input(StringRef name, const CPPType &type)
+  {
+    this->input(name, MFDataType::ForSingle(type));
+  }
+  template<typename T> void vector_input(StringRef name)
+  {
+    this->vector_input(name, CPPType::get<T>());
+  }
+  void vector_input(StringRef name, const CPPType &base_type)
+  {
+    this->input(name, MFDataType::ForVector(base_type));
+  }
+  void input(StringRef name, MFDataType data_type)
+  {
+    data_.param_names.append(name);
+    data_.param_types.append(MFParamType(MFParamType::Input, data_type));
+
+    switch (data_type.category()) {
+      case MFDataType::Single:
+        data_.param_data_indices.append(virtual_span_count_++);
+        break;
+      case MFDataType::Vector:
+        data_.param_data_indices.append(virtual_array_span_count_++);
+        break;
+    }
+  }
+
+  /* Output Parameter Types */
+
+  template<typename T> void single_output(StringRef name)
+  {
+    this->single_output(name, CPPType::get<T>());
+  }
+  void single_output(StringRef name, const CPPType &type)
+  {
+    this->output(name, MFDataType::ForSingle(type));
+  }
+  template<typename T> void vector_output(StringRef name)
+  {
+    this->vector_output(name, CPPType::get<T>());
+  }
+  void vector_output(StringRef name, const CPPType &base_type)
+  {
+    this->output(name, MFDataType::ForVector(base_type));
+  }
+  void output(StringRef name, MFDataType data_type)
+  {
+    data_.param_names.append(name);
+    data_.param_types.append(MFParamType(MFParamType::Output, data_type));
+
+    switch (data_type.category()) {
+      case MFDataType::Single:
+        data_.param_data_indices.append(span_count_++);
+        break;
+      case MFDataType::Vector:
+        data_.param_data_indices.append(vector_array_count_++);
+        break;
+    }
+  }
+
+  /* Mutable Parameter Types */
+
+  template<typename T> void single_mutable(StringRef name)
+  {
+    this->single_mutable(name, CPPType::get<T>());
+  }
+  void single_mutable(StringRef name, const CPPType &type)
+  {
+    this->mutable_(name, MFDataType::ForSingle(type));
+  }
+  template<typename T> void vector_mutable(StringRef name)
+  {
+    this->vector_mutable(name, CPPType::get<T>());
+  }
+  void vector_mutable(StringRef name, const CPPType &base_type)
+  {
+    this->mutable_(name, MFDataType::ForVector(base_type));
+  }
+  void mutable_(StringRef name, MFDataType data_type)
+  {
+    data_.param_names.append(name);
+    data_.param_types.append(MFParamType(MFParamType::Mutable, data_type));
+
+    switch (data_type.category()) {
+      case MFDataType::Single:
+        data_.param_data_indices.append(span_count_++);
+        break;
+      case MFDataType::Vector:
+        data_.param_data_indices.append(vector_array_count_++);
+        break;
+    }
+  }
+
+  /* Context */
+
+  /** This indicates that the function accesses the context. This disables optimizations that
+   * depend on the fact that the function always performers the same operation. */
+  void depends_on_context()
+  {
+    data_.depends_on_context = true;
+  }
+};
+
+}  // namespace blender::fn
+
+#endif /* __FN_MULTI_FUNCTION_SIGNATURE_HH__ */