The workspace on which to create the variable.
Optionalopt_callback: (_0: string) => anyA callback. It will be passed an acceptable new variable name, or null if change is to be aborted (cancel button), or undefined if an existing variable was chosen.
Optionalopt_type: stringThe type of the variable like 'int', 'string', or ''. This will default to '', which is a specific type.
Handles "Create Variable" button in the default variables toolbox category. It will prompt the user for a variable name, including re-prompts if a name is already in use among the workspace's variables.
Custom button handlers can delegate to this function, allowing variables types and after-creation processing. More complex customization (e.g., prompting for variable type) is beyond the scope of this function.