Page 217	Table of Contents	Index	Page 219
	Chapters
	1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 A, B, C, D, E

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CHAPTER 23. PRESENTATION TYPES

function is called with two arguments, the name of a type and a presentation type specifier
for that type with the parameters and options filled in. function has dynamic extent; its two
arguments are permitted to have dynamic extent. The traversal of the type lattice is done in the
order specified by the CLOS class precedence rules, and visits each type in the lattice exactly
once.

=> presentation-type-direct-supertypes type [Function]
Returns a sequence consisting of the names of all of the presentation types that are direct super-
types of the presentation type specifier type, or nil if type has no supertypes. The consequences
of modifying the returned sequence are unspecified.

=> find-presentation-type-class name &optional (errorp t) environment [Function]
Returns the class corresponding to the presentation type named name, which must be a symbol
or a class object. errorp and environment are as for find-class.

=> class-presentation-type-name class &optional environment [Function]
Returns the presentation type name corresponding to the class class. This is essentially the
inverse of find-presentation-type-class. environment is as for find-class.

=> default-describe-presentation-type description stream plural-count [Function]
Performs the default actions for describe-presentation-type, notably pluralization and prepend-
ing an indefinite article if appropriate. description is a string or a symbol, typically the :description
presentation type option or the :description option to define-presentation-type. plural-
count is as for describe-presentation-type.

=> make-presentation-type-specifier type-name-and-parameters &rest options [Function]
A convenient way to assemble a presentation type specifier with only non-default options in-
cluded. This is only useful for abbreviation expanders, not for :inherit-from. type-name-and-
parameters is a presentation type specifier, which must be in the (type-name parameters...)
form. options are alternating keywords and values that are added as options to the presentation
type specifier, except that if a value is equal to type-name's default, that option is omitted,
producing a more concise presentation type specifier.

23.4 Typed Output

An application can specify that all output done within a certain dynamic extent should be
associated with a given Lisp object and be declared to be of a specified presentation type.
The resulting output is saved in the window's output history as a presentation. Specifically, the
presentation remembers the output that was performed (by saving the associated output record),
the Lisp object associated with the output, and the presentation type specified at output time.
The object can be any Lisp object.

=> with-output-as-presentation (stream object type &key modifier single-box allow-sensitive-

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Page 217	Table of Contents	Index	Page 219
	Chapters
	1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30 A, B, C, D, E