This document discusses a programming environment called Loop that is designed to support a prototype-based introduction to object-oriented programming (OOP) for students who have only previously learned structured programming. Loop aims to ease the paradigm shift by starting with a custom environment that delays introducing classes and inheritance, instead focusing on messages, objects, and their interactions through a live object diagram and explicit differentiation between objects and references.

1. A programming environment
supporting a prototype-based
introduction to OOP
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2. CONTEXT
First OOP course
Previous knowledge in structured
programming (PASCAL)
Tight schedule
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3. PROBLEM
Paradigm shift
A lot of new “stuff” to learn in order to
get a first working program
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4. EXAMPLE IN JAVA
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5. EXAMPLE IN SMALLTALK
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6. MOTIVATION
Focus on:
Messages
Objects
Rich interaction between them
Polymorphism
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7. SOLUTION
Start with a custom programming
environment
Delay the introduction of classes and
inheritance
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8. WHAT ABOUT SELF?
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9. WHAT ABOUT SELF?
Traits, prototypes, parent slots, etc.
GUI is not familiar to the students
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10. FEATURES
Definition and usage of objects
Multiple object environments
Live object diagrams
Explicit diferentiation between objects
and references
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11. EXAMPLE IN LOOP
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12. TOWARDS CLASSES
saphira >> eat: aThing
self weight: self weight + aThing weight.
arthur >> weight
^yearsInThrone * 666
daisy >> weight
^732
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13. TOWARDS CLASSES
Dragon >> eat: aThing
self weight: self weight + aThing weight.
King >> weight
^yearsInThrone * 666
ScottishHairyCow >> weight
^732
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14. EXPERIENCE
WITHOUT WITH
Quarter Pass Rate
100
2011 Q1 84,62%
2010 Q2 68,42% 80
2010 Q1 69,76%
60
2009 Q2 80,95%
2008 Q2 66,67% 40
2008 Q1 74,07%
20
2007 Q2 73,33%
2006 Q2 75,00% 0
Pass Rate
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15. CONCLUSIONS
More time for the important concepts
More time for more complex exercises
Concrete to abstract learning path
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16. QUESTIONS
?
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