Date compatible Function from Oracle to Postgres

Question

I am trying to convert the below definition to Postgres.

Current Oracle code:

PROCEDURE Run_All (inDate DATE DEFAULT SYSDATE) IS

In Postgres I used different versions:

1.  CREATE OR REPLACE FUNCTION ssp2_pcat.gen_fios_xml$run_all (indate timestamp(0) DEFAULT CURRENT_DATE) 

2.  CREATE OR REPLACE FUNCTION ssp2_pcat.gen_fios_xml$run_all (indate timestamp without timezone DEFAULT ('now'::text)::date) 

3.  CREATE OR REPLACE FUNCTION ssp2_pcat.gen_fios_xml$run_all (indate date DEFAULT ('now'::text)::date) 

4.  CREATE OR REPLACE FUNCTION ssp2_pcat.gen_fios_xml$run_all (indate timestamp(0) DEFAULT CURRENT_TIMESTAMP::timestamp(0)) 

But still it's throwing an error as below:

ERROR:  column "timestamp" does not exist
LINE 1: SELECT TIMESTAMP
               ^
QUERY:  SELECT TIMESTAMP
CONTEXT:  PL/pgSQL function "gen_fios_xml$run_all"(date) line 13 during statement block local variable initialization
SQL state: 42703

What would be the right way to convert, am I missing something in Postgres? Any update is absolutely appreciated!