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Clarify that RangeTblEntry.lateral reflects whether LATERAL was
specified in the statement (as opposed to whether lateralness is
implicit).  Also, the list of applicable entry types was incomplete.

Reviewed-by: Andrew Dunstan <andrew@dunslane.net>
Discussion: https://www.postgresql.org/message-id/flat/4b27fc50-8cd6-46f5-ab20-88dbaadca645@eisentraut.org

src/include/nodes/parsenodes.h

@@ -1197,7 +1197,7 @@ typedef struct RangeTblEntry
 	 */
 	Alias	   *alias;			/* user-written alias clause, if any */
 	Alias	   *eref;			/* expanded reference names */
-	bool		lateral;		/* subquery, function, or values is LATERAL? */
+	bool		lateral;		/* was LATERAL specified? */
 	bool		inFromCl;		/* present in FROM clause? */
 	List	   *securityQuals;	/* security barrier quals to apply, if any */
 } RangeTblEntry;