Topic: notations for object access

topics > computer science > data > Group: access to data

programming notation
access to components of a data object
access to objects by a path
uniform reference to data


Access notation indicates a component of a data object. The most common are dot notations for accessing record components, and bracketed indices for accessing arrays. Access notation can be chained to indicate an accessing path. Up-arrow is used for dereferencing a pointer. Dot notation was first used in decimal notation. Knuth (knutDE_73) has noted that dot notation doesn't read well (i.e., 'Name.component' for the name's component). He feels that 'component (name)' fits mathematical phraseology, emphasizes the component, and indicates that 'name' is a varying entity. The language L* (grayJC_73) uses dot notation as (cbb 5/80)
Subtopic: natural reference to property up

Quote: the nectar property of a card named flower is "nectar of flower" or "flower's nectar" [»paneJF9_2002]

Subtopic: structures and arrays up

Quote: in PL/1, structures and arrays can be intermixed, e.g., a. b(10) [»sammJE_1969, OK]

Subtopic: style up

Quote: prefer info(p) over because info() has a fixed meaning while p is variable [»knutDE_1973]

Subtopic: component and pointer selection up

QuoteRef: grayJC_1973 ;;169 component selection by selector.item
QuoteRef: demeA3_1979 ;;21 "The form [Var[val] Denotation . Id is treated as shorthand for T $ Id ( [Var/Val]Denotation) where T is the type of the given denotation
QuoteRef: wulfWA6_1976 ;;20 ref by function (element, parameters) or element. function (params)
QuoteRef: wirtN1_1971 ;;46 in Pascal, variable access by b[red] or U.realpart or file_name^ or pointer^

Related Topics up

Group: programming notation   (14 topics, 221 quotes)
Topic: access to components of a data object (4 items)
Topic: access to objects by a path (13 items)
Topic: uniform reference to data
(34 items)

Updated barberCB 9/04
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