function command( repl ) {
	return onCommand;

	/**
	* Deletes user-defined variables in the current workspace.
	*
	* @private
	* @param {Options} [options] - function options
	* @param {(RegExp|ArrayLikeObject)} [options.include] - name inclusion filter
	* @param {(RegExp|ArrayLikeObject)} [options.exclude] - name exclusion filter
	*/
	function onCommand( options ) {
		var opts;
		if ( arguments.length ) {
			opts = options;
		} else {
			opts = {};
		}
		repl._context.clearWorkspace( repl._currentWorkspace, opts );
	}
}
Returns a callback to be invoked upon calling the `clearVars` command.

@private
@param {REPL} repl - REPL instance
@returns {Function} callback