Add structure for proton-boron fusion module (#2217)

* Add structure for proton-boron fusion module

* Fix clang compile error

* Generalize structure for other nuclear fusion types

* Workaround: try to use std::vectors to fix clang compile error

* Simplify workaround for clang

* Rebase on 2245 and add empty particle creation functor

* Apply suggestions from code review

Co-authored-by: Axel Huebl <axel.huebl@plasma.ninja>

* Add couple of consts and runtime assert

* Add another const

Co-authored-by: Axel Huebl <axel.huebl@plasma.ninja>

1 files changed, 30 insertions, 0 deletions

diff --git a/Source/Particles/Collision/BinaryCollision/BinaryCollisionUtils.H b/Source/Particles/Collision/BinaryCollision/BinaryCollisionUtils.H
new file mode 100644
index 000000000..c20e9716c
--- /dev/null
+++ b/Source/Particles/Collision/BinaryCollision/BinaryCollisionUtils.H
@@ -0,0 +1,30 @@
+/* Copyright 2021 Neil Zaim
+ *
+ * This file is part of WarpX.
+ *
+ * License: BSD-3-Clause-LBNL
+ */
+
+#ifndef BINARY_COLLISION_UTILS_H_
+#define BINARY_COLLISION_UTILS_H_
+
+#include <string>
+
+#include "Particles/MultiParticleContainer.H"
+
+enum struct CollisionType { ProtonBoronFusion, Undefined };
+
+enum struct NuclearFusionType { ProtonBoron, Undefined };
+
+namespace BinaryCollisionUtils{
+
+    NuclearFusionType get_nuclear_fusion_type (const std::string collision_name,
+                                               MultiParticleContainer const * const mypc);
+
+    CollisionType get_collision_type (const std::string collision_name,
+                                      MultiParticleContainer const * const mypc);
+
+    CollisionType nuclear_fusion_type_to_collision_type (const NuclearFusionType fusion_type);
+}
+
+#endif // BINARY_COLLISION_UTILS_H_