1. OOP Class Lawrence D’Antonio Lecture 2 History of OOP and C++

2. OOPL  Simula  Smalltalk  C++  Java  Python  C#  Eiffel  Ruby

3. More OOPL  Dylan  Modula 3  Self  Sather  Forté  Objective C  Object Pascal  Visual Basic  Perl

4. More OOPL  PHP  REBOL  CLOS  Delphi  COBOL  Prolog  Ada DDDD

5. History of Simula  Developed by Kristen Nygaard and Ole- Johan Dahl.  Carried out at the Norwegian Computing Center.  Designed as a system description language, built on ALGOL 60, to implement simulations.  Development was begun in 1961, leading to the definition of Simula 1 in 1963-4.

6. History of Simula – Part 2   Process concept: Active customers moving through a passive network. System = Set of interacting processes   In 1965, Tony Hoare introduced the concept of a record class for handling records.   Nygaard and Dahl introduce the concept of processes with layers in Simula 67.

7. Simula 67 features   Introduced classes, subclasses, virtual methods   Garbage collection

8. Simula example Class Rectangle (Width, Height); Real Width, Height; ! Class with two parameters; Begin Real Area, Perimeter; ! Attributes; Procedure Update; ! Methods (Can be Virtual); Begin Area := Width * Height; Perimeter := 2*(Width + Height) End of Update; Boolean Procedure IsSquare; IsSquare := Width=Height; Update; ! Life of rectangle started at creation; OutText("Rectangle created: "); OutFix(Width,2,6); OutFix(Height,2,6); OutImage End of Rectangle; End of Rectangle

9. History of Smalltalk  Developed at Xerox PARC in 1971-2.  Developed by Alan Kay et al to be a compact powerful OOPL, analogous to LISP. Alan KayAlan Kay  Designed in parallel to the Dynabook project.  Public release in 1980 (Smalltalk-80).

10. Smalltalk features  Pure object-oriented  Dynamically and strongly typed  Reflective language (self-modifying)  Garbage collection  Everything is an object. Classes are instances of metaclasses.

11. Smalltalk example | x y className methodName | className := 'Foo'. methodName := 'hello'. x := (Compiler evaluate: className). (x isKindOf: Class) ifTrue: [ y := x new. (y respondsTo: methodName asSymbol) ifTrue: [ y perform: methodName asSymbol ]

12. History of Ada  In 1975, DoD put out a request for a language meeting certain goals (Steelman requirements). No existing language met these goals, so a new language was created. Steelman  Jean Ichbiah created the language Ada – 83 to meet these goals.  Ada – 95 was the next installment of the language, designed by S. Tucker Taft.

13. Ada Features  Exception handling  Modularity  Statically and strongly typed.  Generics  Dynamic binding  Inheritance  Garbage collection

14. Ada Example with dates; use dates; -- definition of type date package persons is type person is tagged record name :string(1..10); dob :date; salary :float := 0.0; end record; procedure employ(someone:in out person); procedure dismiss(someone:in out person); procedure pay_raise(someone:in out person); end persons;

15. Ada Example, Part 2 with persons; use persons; package managers is type manager is new person with record master_key_code :string(1..10); end record; procedure allocate_master_key( someone:in out manager; code :in string); procedure pay_raise(someone:in out person); end managers;

16. Python History   Developed in late 1980’s by Guido van Rossum. Open source.   Published in 1991.   Version 1.0 released in 1994.   Versions 1.6 and 2.0 released in 2000.   GNU GPL compatible since 2001   Python 3.0 (Python 3000) released in alpha version in 2007.

17. Python Features   Simple, easy to learn language   Dynamically and strongly typed   Metaclasses   Exception handling   Garbage collection

18. Python Example class Stack: def __init__(self): # Initialize the stack self.stack = [ ] def push(self,object): self.stack.append(object) def pop(self): return self.stack.pop() def length(self): return len(self.stack) #Example s = Stack() # Create a stack s.push("Dave") # Push some things onto it s.push(42) s.push([3,4,5]) x = s.pop() # x gets [3,4,5] y = s.pop() # y gets 42 del s # Destroy s

19. C++ History   Bjarne Stroustrup began working on the idea of an efficient OOPL in 1979 at AT&T Labs.   Started developing C with Classes, that combined features of Simula and C.   1980 version had classes, inheritance, public/private, ctors and dtors, friends, type checking, inline, overloading assignment operator

20. C++ History – Part 2   Finished the first C++ compiler, Cfront, in 1983. Cfront was written in C++, but converted code into C.   In 1983, Rick Mascitti suggested the name C++ for the language.   Added features: virtual functions, overloading, references, const, operator new

21. C++ History – Part 3   In 1985, published first edition of The C++ Programming Language and version 1.0 of C++ released.   In 1989, version 2.0 released. Added features: multiple inheritance, abstract classes, const member functions, protected members.   In 1990, The Annotated C++ Reference Manual was published.

22. C++ History – Part 4   Templates proposed in 1988.   Exception handling designed, with Andrew Koenig, in 1989.   I/O library designed by Jerry Schwarz and Koenig for version 2.0.   X3J16 standardization committee formed in December 1989.

23. Standard Template Library History   In 1987 Alex Stepanov and David Musser, at GE R&D, developed a generic list processing library for Ada.   Stepanov presented his idea of a generic library for C++ at the November 1993 meeting of X3J16.   The library design was developed (with Meng Lee) and approved at the March 1994 meeting.

24. C++ History – Part 5   C++ standard was approved on November 14, 1997.   Corrected version of the standard was approved in 2003.

25. C++ - the Future   Library Technical Report 1 (TR1) released in 2005. Suggestions such as smart pointers, metaprogramming, improved functors, improved numerical functions, regular expressions, fixed size array class, hash tables. Expected to be adopted for next version of standard.