CLHS: System Class CONS (original) (raw)

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System Class CONS

Class Precedence List:

cons, list, sequence, t

Description:

A cons is a compound object having two components, called the car and cdr. These form a dotted pair. Each component can be any object.

Compound Type Specifier Kind:

Specializing.

Compound Type Specifier Syntax:

cons [car-typespec [cdr-typespec]]

Compound Type Specifier Arguments:

_car-typespec_---a type specifier, or the symbol *. The default is the symbol *.

_cdr-typespec_---a type specifier, or the symbol *. The default is the symbol *.

Compound Type Specifier Description:

This denotes the set of conses whose car is constrained to be of type car-typespec and whose cdr is constrained to be of type cdr-typespec. (If either car-typespec or cdr-typespec is *, it is as if the type t had been denoted.)

See Also:

Section 2.4.1 (Left-Parenthesis), Section 22.1.3.5 (Printing Lists and Conses)

The following X3J13 cleanup issue, not part of the specification, applies to this section:

• CONS-TYPE-SPECIFIER:ADD

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