ModuleImportExtension is a helper class used for QJSEngine to extend its functionality by adding a module import function in engine's global scope. This function allows to import JS modules in runtime while evaluating a script.
JavaScript modules allow you to break up your code into separate files. This makes it easier to maintain the code-base.
JavaScript modules rely on the import and export statements. However, Qt Script does not support import statement and only provide a function QJSEngine::importModule(). That is, you can't import modules from your JS script code, only by using the C++ backend functionality.
ModuleImportExtension class inserts a module import function in QJSEngine global scope that provides you import modules in the similar way like it is with JS import statement.
The script module.js is the example of a module.
The script main.js uses a function importModule() to import module.js. The first argument is a relative path to the module, the second argument is an alias for the module space.
If you want to run the project succesfully, you have to put all .js files in an application's current directory (build-moduleimportextension-Desktop_Qt....)
The example of importing modules with ModuleImportExtension is shown in main.cpp.
It is convenient to use because you have to insert only one file (moduleimportextension.h) in your project.