Re: Object-relational impedence

From: Robert Martin <>
Date: Thu, 6 Mar 2008 00:42:42 -0600
Message-ID: <2008030600424297801-unclebob_at_objectmentorcom>

On 2008-03-05 03:24:37 -0600, S Perryman <> said:

> Robert Martin wrote:

>> On 2008-03-03 18:34:39 -0600, Marshall <> said:

>>> In SQL, if I have two relations with x and y int columns, I can
>>> union them, or join on them, or whatever. There is no way,
>>> in fact, to forbid such a thing, just like in Java there is no way
>>> to allow such a thing.

>> You are confusing OO with static typing. In OO languages like Ruby, 
>> Python, or Smalltalk you can pass any object to any function 
>> irrespective of type.

> And you (both) are equating the (strong) typing model of Simula as the
> only strong typing model.

You presume too much. Type inferrence can be nearly as flexible as dynamic typing.

> Go and look at Functional prog langs etc for
> examples of how Marshalls' gripe would be done in a type-safe manner.


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Received on Thu Mar 06 2008 - 07:42:42 CET

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