PROGRAMMING LANGUAGE DESIGN CONCEPTS

PROGRAMMING LANGUAGE DESIGN CONCEPTS
David A. Watt, University of Glasgow with contributions by

William Findlay, University of Glasgow

Copyright  2004

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ecursive types in general 2.5 Type systems 2.5.1 Static vs dynamic typing 2.5.2 Type equivalence 2.5.3 The Type Completeness Principle 2.6 Expressions 2.6.1 Literals 2.6.2 Constructions 2.6.3 Function calls 2.6.4 Conditional expressions 2.6.5 Iterative expressions 2.6.6 Constant and variable accesses

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Contents

2.7

Implementation notes 2.7.1 Representation of primitive types 2.7.2 Representation of Cartesian products 2.7.3 Representation of arrays 2.7.4 Representation of disjoint unions 2.7.5 Representation of recursive types Summary Further reading Exercises 3 Variables and storage 3.1 Variables and storage 3.2 Simple variables 3.3 Composite variables 3.3.1 Total vs selective update 3.3.2 Static vs dynamic vs flexible arrays 3.4 Copy semantics vs reference semantics 3.5 Lifetime 3.5.1 Global and local variables 3.5.2 Heap variables 3.5.3 Persistent variables 3.6 Pointers 3.6.1 Pointers and recursive types 3.6.2 Dangling pointers 3.7 Commands 3.7.1 Skips 3.7.2 Assignments 3.7.3 Proper procedure calls 3.7.4 Sequential commands 3.7.5 Collateral commands 3.7.6 Conditional commands 3.7.7 Iterative commands 3.8 Expressions with side effects 3.8.1 Command expressions 3.8.2 Expression-oriented languages 3.9 Implementation notes 3.9.1 Storage for global and local variables 3.9.2 Storage for heap variables 3.9.3 Representation of dynamic and flexible arrays Summary Further reading