Add map conversions

closes #57

cheatsheet.md

@@ -90,6 +90,13 @@ A helper function exists for strongly typed and ChaiScript `Vector` function con
 chai.add(chaiscript::vector_conversion<std::vector<int>>());
 ```
 
+A helper function also exists for strongly typed and ChaiScript `Map` function conversion definition:
+
+```
+chai.add(chaiscript::map_conversion<std::map<std::string, int>>());
+```
+
+
 This allows you to pass a ChaiScript function to a function requiring `std::vector<int>`
 
 ## Adding Objects

include/chaiscript/dispatchkit/type_conversions.hpp

@@ -592,6 +592,24 @@ namespace chaiscript
       return chaiscript::make_shared<detail::Type_Conversion_Base, detail::Type_Conversion_Impl<decltype(func)>>(user_type<std::vector<Boxed_Value>>(), user_type<To>(), func);
     }
 
+  template<typename To>
+    Type_Conversion map_conversion()
+    {
+      auto func = [](const Boxed_Value &t_bv) -> Boxed_Value {
+        const std::map<std::string, Boxed_Value> &from_map = detail::Cast_Helper<const std::map<std::string, Boxed_Value> &>::cast(t_bv, nullptr);
+
+        To map;
+        for (const std::pair<std::string, Boxed_Value> &p : from_map) {
+          map.insert(std::make_pair(p.first, detail::Cast_Helper<typename To::mapped_type>::cast(p.second, nullptr)));
+        }
+
+        return Boxed_Value(std::move(map));
+      };
+
+      return chaiscript::make_shared<detail::Type_Conversion_Base, detail::Type_Conversion_Impl<decltype(func)>>(user_type<std::map<std::string, Boxed_Value>>(), user_type<To>(), func);
+    }
+
+
 }
 
 

unittests/compiled_tests.cpp

@@ -872,6 +872,7 @@ struct Returned_Converted_Config
 };
 
 
+
 TEST_CASE("Return of converted type from script")
 {
   chaiscript::ChaiScript chai;
@@ -914,3 +915,27 @@ TEST_CASE("Return of converted type from script")
 }
 
 
+int get_value_a(const std::map<std::string, int> &t_m)
+{
+  return t_m.at("a");
+}
+
+
+TEST_CASE("Map conversions")
+{
+  chaiscript::ChaiScript chai;
+  chai.add(chaiscript::map_conversion<std::map<std::string, int>>());
+  chai.add(chaiscript::fun(&get_value_a), "get_value_a");
+
+  const auto c = chai.eval<int>(R"(
+    var m = ["a": 42];
+    get_value_a(m);
+  )");
+
+  CHECK(c == 42);
+
+}
+
+
+
+