Transcript 13. Summary, Trends, Research

13. Summary, Trends, Research
PS — Summary, Trends, Research ...
Summary, Trends, Research ...
Summary: functional, logic and object-oriented
languages
> Research: ...
>
www.iam.unibe.ch/~scg
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C and C++
Good for:
> systems programming
> portability
Bad for:
> learning (very steep learning curve)
> rapid application development
> maintenance
Trends:
> increased standardization
> generative programming
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Functional Languages
Good for:
> equational reasoning
> declarative programming
Bad for:
> OOP
> explicit concurrency
> run-time efficiency (although constantly improving)
Trends:
> standardization: Haskell, “ML 2000”
> extensions (concurrency, objects): Facile, “ML 2000”,
UFO ...
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Lambda Calculus
Good for:
> simple, operational foundation for sequential
programming languages
Bad for:
> programming
Trends:
> object calculi
> concurrent, distributed calculi (e.g., pi calculus, “join”
calculus ...)
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Type Systems
Good for:
> catching static errors
> documenting interfaces
> formalizing and reasoning about domains of functions
and objects
Bad for:
> reflection; self-modifying programs
Trends:
> automatic type inference
> reasoning about concurrency and other side effects
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Polymorphism
Good for:
> parametric good for generic containers
> subtyping good for frameworks (generic clients)
> overloading syntactic convenience (classes in Haskell,
overloading in Java)
> coercion convenient, but may obscure meaning
Bad for:
> local reasoning
> optimization
Trends:
> combining subtyping, polymorphism and overloading
> exploring alternatives to subtyping (“matching”)
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Denotational Semantics
Good for:
> formally and unambiguously specifying languages
> sequential languages
Bad for:
> modelling concurrency and distribution
Trends:
> “Natural Semantics” (inference rules vs. equations)
> concurrent, distributed calculi
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Logic Programming
Good for:
> searching (expert systems, graph & tree searching ...)
> symbolic interpretation
Bad for:
> debugging
> modularity
Trends:
> constraints
> concurrency
> modules
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Object-Oriented Languages
Good for:
> domain modelling
> developing reusable frameworks
Bad for:
> learning (steep learning curve)
> understanding (hard to keep systems well-structured)
> semantics (no agreement)
Trends:
> component-based software development
> aspect-oriented programming
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Scripting Languages
Good for:
> rapid prototyping
> high-level programming
> reflection; on-the-fly generation and evaluation of programs
> gluing components from different environments
Bad for:
> type-checking; reasoning about program correctness
> performance-critical applications
Trends:
> replacing programming as main development paradigm
> scriptable applications
> graphical “builders” instead of languages
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License
>
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