Quick question why must a file be saved before you can make a drawing from it?
If the drawing does not have a reference to the part then it cannot know where it is pulling the information from for the drawing.
The only way I know of to do what you are looking for is to initially save the part in order to create the drawing and once you are finished save the drawing as a detached drawing. This way you are able to delete the part if you wish.
Your drawing will be referencing the file therefore it must have a file path in order to reference your part/assembly you are creating a drawing of.
Why not have the option to create a drawing without initially referencing the model part.
Then if you want to save it then have it reference the model.
I've been using SolidWorks for over 10 years now and from time to time I just want a quick drawing where the model doesn't need to be saved.
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