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Topic: variable as reference to storage
topics >
computer science >
data >
aliasing
Topic:
data record
Topic:
pointers to data
Topic:
primitive data type as memory
Topic:
replacement as setting a reference to a value
Topic:
variable as reference to a value
Summary
A variable is the address of a storage cell which contains the variable's value. The address may be the contents of another storage cell. The variable identifies an address which identifies a value. It models 'von Neumann' computers with variables identified as memory location. (cbb 5/80)If a variable is a place holder, then have problems with self-reference and aliasing. [Backus 72]
Subtopic: problems with place holders
Quote: with storage semantics, a variable is a storage location with a value; pointers, sharing or aliasing, and mutable values; e.g., FORTRAN, C [»cleaJC_1986] Quote: storage semantics is more common than value or reference semantics; represent objects by containment or by references, whichever works better [»taivA4_1993] Quote: a variable is a set of locations that represent a mathematical value according to a convention determined by the variable's type; v is a member of T, and T contains v Quote: what is the meaning of a name in a program? In Bliss, it is a location. In Algol 68, it is a location that is automatically converted to a value. In C, it is a value. [»ritcDM_1996] Quote: a variable denotes a fixed address whose content is its value [»straC3_1973] Quote: Turing and Newman explained to Williams and Kilburn how numbers live in houses with addresses [»copeBJ_1999] QuoteRef: hehnEC_1977a ;;2 cell computer "A cell can hold a value and is denoted by an identifier or name QuoteRef: richM_1974 ;;11 each storage cell holds binary value (right hand side valve) with lvalue address of same size. only primitive object QuoteRef: richM_1974 ;;12 in BCPL a variable is bound to a storage cell QuoteRef: backJ_1972 ;;12 the areas or problems are accessing and modifying variables (scope and side effects selection element functions
Quote: if variables are place holders then problems with self-reference and aliasing [»backJ_1972, OK] Quote: storage semantics in object-oriented languages leads to problems with copying, destruction, and comparison [»taivA4_1993]
Topic: aliasing (28 items)
Topic: data record (57 items)
Topic: pointers to data (55 items)
Topic: primitive data type as memory (29 items)
Topic: replacement as setting a reference to a value (10 items)
Topic: variable as reference to a value
(21 items)