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Apple Newton Programmer’s Newton 2.0 (for Newton 2.0) User Manual

Page 912

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G L O S S A R Y

GL-4

item frame

The frame that encapsulates a

routed (sent or received) object and that is stored
in the In/Out Box soup.

lexical dictionary

A list of valid grammars,

each specifying the format of an entity to be
recognized, such as a date, time, phone number
or currency value. See also enumerated
dictionary
and grammar.

line

A shape defined by two points: the current

x and y location of the graphics pen and the x
and y location of its destination.

local

A variable whose scope is the function

within which it is defined. You use the

local

keyword to explicitly create a local variable
within a function.

magic pointer

A constant that represents a

special kind of reference to an object in the
Newton ROM. Magic pointer references are
resolved at run time by the operating system,
which substitutes the actual address of the ROM
object for the magic pointer reference.

meeting

An entry in the Dates application for

a specific time during the day. People can be
invited and the meeting can be scheduled for a
particular location.

message

A symbol with a set of arguments. A

message is sent using the message send syntax
frame

:

messageName

()

, where the message

messageName is sent to the
receiver frame.

method

A function object in a frame slot that

is invoked in response to a message.

name reference

A frame that contains a soup

entry or an alias to a soup entry, often, though
not necessarily, from the Names soup. The
frame may also contain some of the individual
slots from the soup entry.

NewtonScript heap

An area of RAM used by

the system for dynamically allocated objects,
including NewtonScript objects.

nil

A value that indicates nothing, none, no,

or anything negative or empty. It is similar to

(void*)0

in C. The value

nil

represents

“false” in Boolean expressions; any other value
represents “true.”

object

A typed piece of data that can be an

immediate, array, frame, or binary object. In
NewtonScript, only frame objects can hold
methods and receive messages.

option frame

A frame passed as a parameter

to an endpoint method that selects the
communication tool to use; controls its
configuration and operation; and returns result
code information from the endpoint method.

origin

The coordinates of the top-left corner

of a view, usually (0, 0). The origin can be
shifted, for example, to scroll the contents of
a view.

output spec

A special type of callback spec

used with an endpoint method. An output spec
contains a few additional slots that allow you to
pass special protocol flags and to define how the
data being sent is translated.

oval

A circular or elliptical shape defined by

the bounding rectangle that encloses it.

package

The unit in which software can be

installed on and removed from the Newton.
A package consists of a header containing the
package name and other information, and one or
more parts containing the software.

package file

A file that contains downloadable

Newton software.

package store

See store part.

parent

A frame referenced through the

_parent

slot of another frame. With regard to

views, a parent view encloses its child views.