Where are user defined functions stored?

If I write a rule, I can easily see it by doing

select * from pg_rules;

and I also get to see all the rules I have created for my database.  How can I easily get to see the definition of a
userdefined function please?  I've searched through the online manual but failed to find the answer.
 

TAI
Hilary

Hilary Forbes
The DMR Information and Technology Group  (www.dmr.co.uk)
Direct tel 01689 889950 Fax 01689 860330 
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