Are parameters in a PL/SQL Stored Procedure "IN" by default?

Rephrasing the question: Are this two code snippets different in any way?

CREATE OR REPLAC开发者_开发百科E PROCEDURE 
ASSIGN_EMAIL(E_NO INT, F_NAME VARCHAR2, L_NAME VARCHAR2)

CREATE OR REPLACE PROCEDURE 
ASSIGN_EMAIL(E_NO IN INT, F_NAME IN VARCHAR2, L_NAME IN VARCHAR2)

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Yes, IN is the default. Check table 8.1 in the Oracle PL/SQL subprogram docs.