Importing module signatures ?

[David Teller <David.Teller@univ-orleans.fr>]

   Hi everyone,
 I'm trying to extend a module into another module, preferably without
using functors. For the implementation, I have no problem, simply using
"include" does what I need. For the signature, however, I'm obviously
doing something wrong:
        
        module A =
        struct
        	include String
        end
        
        => works
        
        module A :
        sig
          include String
        end
        
        => "Unbound module type String"
        
It seems that String is the name of the module structure itself rather
than its signature. But what is the name of the signature ?
        
Thanks,
 David
-- 
David Teller ------------------------------------------
Security of Distributed Systems -----------------------
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