Ravel Classes

The Ravel library is written in C++, and compiled to Javascript via the emscripten compiler. There are some limitations with the Javascript interface generated by the current emscripten implementation:

• C++ objects created by the system must be explicitly deleted by calling their delete method, otherwise a memory leak results. Unfortunately, Javascript has no concept of finaliser that is present in other garbage collected languages that would help here.
• C++ methods returning complex data types will generate a new C++ object, that needs to be deleted as well. Strings are an exception, in that they are simply converted into Javascript strings. In the following documentation, it will be noted if the returned object needs to be deleted.
• C++ methods returning a reference do not return a reference object back to Javascript, but instead create a new C++ object that is a copy. Because of this, special reference members are added into containing objects that can be adjusted to point to desired object. Ravel::Handle is an example.
• Method overloading is not supported in Javascript. Overloaded C++ methods must have different names in Javascript (even if the number of arguments differ). In particular, this means that getter/setter methods need distinct names, so we use the get/set Attribute convention here, even if the C++ equivalents are just the attribute name with setter/getter functionality distinguished by argument.
• All C++ classes and other objects are created in the Module namespace.