Oberon

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Oberon

• Oral Exam English

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index

• The creator
• The history
• The use
• The syntax
• An example
• Conclusion

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The creator - Niklaus Wirth

• Swiss computer scientist
• born February 1934
• Academic history
• Electronics Engineering (ETH in Zürich)
• Master degree from Laval University , Canada
• Ph.D from University of California Berkeley

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The creator - Niklaus Wirth

• Assistant professor Comp Science at Stanford
  University and University of Zürich
• Prof Informatics at ETH Zürich
• Chief designer of Algol W, Pascal, Modula,
  Modula-2, and Oberon

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history

• ALGOL 60s
• Pascal 70s (first OO)
• Modula / Modula-2 - 80s (Modules)
• Oberon / Oberon-2 - 80s-90s (OO)

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The use

• Pascals syntax, style
• More power
• Very clear structure
• Object-Oriented
• 20 years experience
• Executable problem
• ?Used for teaching

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The syntax - introduction

• Case sensitive
• Line end ?
• Comment ? ( )

• MODULE Hello
• ( first program )
• IMPORT Out
• PROCEDURE Do
• BEGIN
• Out.String(Hello)
• Out.Ln
• END Do
• END Hello

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The syntax Programme Structure

• MODULE Hello
• ( first program )
• IMPORT Out
• PROCEDURE Do
• BEGIN
• Out.String(Hello)
• Out.Ln
• END Do
• END Hello

• MODULE
• PROCEDURE
• BEGIN
• END
• ? predefined words

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The syntax VAR CONST

• Predefined section
• Marked by VAR
• Varname TYPE
• Assignment operator ?
• constants in CONST section

• PROCEDURE Vartest
• CONST
• numb 6
• VAR
• a INTEGER
• b REAL
• c REAL
• BEGIN
• a 3
• c numba
• Out.Real(c)
• Out.Ln
• END Vartest

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The syntax - Datatypes

• BOOLEAN ? TRUE / FALSE
• CHAR ? ASCII
• SHORTINT ? -128...127
• INTEGER ? -32768...32767
• LONGINT ? -2E9...2E9
• REAL ? -3,4E38...3.4E38

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The syntax Loops / Conditions

• WHILE
• WHILE (var1 lt 3) DO
• var2 var2 1
• END
• REPEAT
• REPEAT
• var2 var2 1
• UNTIL (var1 lt 3)
• LOOP
• LOOP
• var2 var2 1
• EXIT
• END

• IF
• IF (var1 3) THEN
• Out.String(Hurray)
• ELSE
• Out.String(Booh)
• END
• CASE
• CASE var1 OF
• 1 Out.String(1)
• 2 Out.String(2)
• 3 Out.String(3)
• ELSE
• Out.String(none)
• END

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Example GFX engine

• Very powerful language
• Example my GFX engine
• 5 months experience in Oberon
• No other programming background
• Many GFX possibilities

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Example GFX engine

• Dynamic 3D Object
• Rendered by Oberon
• Backface culling
• Z-buffer
• Shading

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Example GFX examples
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Conclusion

• Structured, Compact, Powerful
• Many possible compilers
• Downside Executable files
• Used for teaching

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Thank you for your attention

• Any questions?