Equality operators on NULL values

(in)Equality operators evaluates to NULL when any of their
arguments are NULL as summarized bellow.

NULL=NULL ==> NULL
1=NULL ==> NULL
1=1 ==> t
1=2 ==> f

I have a case where I need to delete rows from table A for records
that are designated in table B. One of the joined colum can have NULL
values. Therefore I need an operator behaving as follows:

NULL=NULL ==> t
1=NULL ==> NULL (or anything else as long as it is not t)
1=1 ==> t
1=2 ==> f

I replaced the use of the = operator with this expression:

nullif(tabA.col_with_nulls, tabB.col_with_nulls) IS NULL

It works correctly but the intent is not that clear.

Is there a stock replacement operator that would behave like
the second truth table?

Regards,
Bertrand.

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