Thinking in FP vs OOP for large scale apps => Re: [plt-scheme] Imperative programming : missing the flow

From: Bill Wood (william.wood3 at
Date: Wed May 16 18:28:33 EDT 2007

On Wed, 2007-05-16 at 17:08 -0400, Matthias Felleisen wrote:
   . . .
> The OO concept predates ADTs from what I can tell by several years.
> When I started reading on ADTs in 1979/80  I think the idea was
> that they could explain notions such as the 1965/66 OO programming
> and Hoare's data types etc. The IBM tech rpts I saw are from the
> very late 60s and early 70s.

The earliest reference I can find to a recognizable OO ancestor is
Simula 67, and I know Hewitt's Actor model also comes in there at around
the same time.  What are you thinking of that came about ca. 1965?

I can find references to ADTs, both algebraic and abstract model, from
around 1973 (Parnas 1972, A Technique for the Specification of Software
Modules; Zilles 1974, Algebraic Specification of Data Types), but
nothing earlier.  In [1] data abstractions specified using the abstract
model approach are recognized as far back as Earley 1971 (Toward an
Understanding of Data Structure).

Even pushing ADTs back to the early 70s, OO before ADT still seems

[1] Barbara Liskov and Stephen Zilles, "An Introduction to Formal
Specifications of Data Abstractions", Chapter 1, Current Trends in
Programming Methodology, vol. 1, Software Specification and Design,
Raymond T. Yeh (ed), 1977.

 -- Bill Wood

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