From this list, choose the version of the TypeScript to use (PhpStorm displays the currently chosen version).
By default, the typescript package from the project's node_modules folder is used.
Bundled: choose this option to use the typescript package that comes bundled with PhpStorm without attempting to find another one.
Select: choose this option to use a custom typescript package instead of the one bundled with PhpStorm. Choose the path to the relevant package in the dialog that opens.
TypeScript Language Service
Select this checkbox to get native support from the TypeScript Language Service according to the up-to-date specifications. As a result:
Syntax and error highlighting is based on the annotations from the TypeScript Language Service.
Completion lists contain both suggestions from the TypeScript Language Service and suggestions calculated by PhpStorm.
Also for projects without tsconfig.json
When this checkbox is selected, the TypeScript Language Service also processes projects that do not contain a tsconfig.json configuration files. In this case, the default scope is the entire project.
Recompile on changes
From this list, choose the scope in which the compiler will work when you click Compile and choose Compile All in the TypeScript Tool Window. The available options are:
VCS Scopes: these scopes are only available if your project is under version control.
Alternatively, click and configure a custom scope in the Scopes dialog that opens.For more details on scopes, see the pages Scopes and Scopes dialog.
In this field, specify the command line options to be passed to the TypeScript Language Service when the tsconfig.json file is not found. See the list of acceptable options at TSC arguments. Note that the