how to make read only schema can select text of procedure,trigger,function, sequence and job on the

 Hi,

My user request read only schema to read all objects of a main schema,

For the table /view is quite straightforward to use "grant select on objects to read_user",

but for the procedure,trigger,function, sequence and job, how can I make read only schema can read text of those objects?

I was test "grant select on all_source to read_user" but it looks not work as I can select main schema function text by sys account, but read_user no returns. 

Regards

Sean