date - date returns integer?

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Should date - date return type integer, not interval?

/* ahammond@test:5432/test =# */ SELECT ('2005-03-04'::timestamp -
'2005-01-01'::date)::interval;
~ interval
- ----------
~ 62 days
(1 row)

/* ahammond@test:5432/test =# */ SELECT ('2005-03-04'::date -
'2005-01-01'::date)::interval;
ERROR:  cannot cast type integer to interval

- --
Andrew Hammond    416-673-4138    ahammond@ca.afilias.info
Database Administrator, Afilias Canada Corp.
CB83 2838 4B67 D40F D086 3568 81FC E7E5 27AF 4A9A
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