Deprecation in 1.x without fix

Description

Using the latest 1.x release, I'm encountering a depreciation warning that IDragEvent is deprecated and will be removed in 2.x in favor of Drag.Event. I think "oh, thanks for the warning, I will change that immediately", and change the code to use Drag.Event, but now get told that it doesn't exist. So I'm left to wonder what the purpose of the depreciation warning was 😅

Reproduce

Import IDragEvent in an editor that gives hints. It will still compile, but your IDE will give you a warning.

Expected behavior

The "in favor of" solution should exist in the 1.x branch, or the warning should be removed.

Context

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JupyterLab version:

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The interface IDragEvent also exists in Lumino 2. along with the deprecation tag.

lumino/packages/dragdrop/src/index.ts

Lines 14 to 20 in 133d872

    
           /** 
        
            * @deprecated 
        
            * 
        
            * #### Notes 
        
            * This interface is deprecated. Use Drag.Event instead. 
        
            */ 
        
           export interface IDragEvent extends Drag.Event {}

So maybe the right answer is to remove the deprecation tag in Lumino 1, as in your alternate suggestion, and allow people to change their code once they upgrade to Lumino 2.

Yes, that's probably the best solution. I know in Python it is possible to differentiate between "this will be deprecated in the future" and "this is currently deprecated ", but I don't think jsdoc tags support that distinction?

	/**
	* @deprecated
	*
	* #### Notes
	* This interface is deprecated. Use Drag.Event instead.
	*/
	export interface IDragEvent extends Drag.Event {}