38.3. aepack
— Conversion between Python variables and AppleEvent data containers¶
The aepack
module defines functions for converting (packing) Python
variables to AppleEvent descriptors and back (unpacking). Within Python the
AppleEvent descriptor is handled by Python objects of built-in type
AEDesc
, defined in module Carbon.AE
.
Note
This module has been removed in Python 3.x.
The aepack
module defines the following functions:
-
aepack.
pack
(x[, forcetype])¶ Returns an
AEDesc
object containing a conversion of Python value x. If forcetype is provided it specifies the descriptor type of the result. Otherwise, a default mapping of Python types to Apple Event descriptor types is used, as follows:Python type
descriptor type
FSSpec
typeFSS
FSRef
typeFSRef
Alias
typeAlias
integer
typeLong (32 bit integer)
float
typeFloat (64 bit floating point)
string
typeText
unicode
typeUnicodeText
list
typeAEList
dictionary
typeAERecord
instance
see below
If x is a Python instance then this function attempts to call an
__aepack__()
method. This method should return anAEDesc
object.If the conversion x is not defined above, this function returns the Python string representation of a value (the repr() function) encoded as a text descriptor.
-
aepack.
unpack
(x[, formodulename])¶ x must be an object of type
AEDesc
. This function returns a Python object representation of the data in the Apple Event descriptor x. Simple AppleEvent data types (integer, text, float) are returned as their obvious Python counterparts. Apple Event lists are returned as Python lists, and the list elements are recursively unpacked. Object references (ex.line 3 of document 1
) are returned as instances ofaetypes.ObjectSpecifier
, unlessformodulename
is specified. AppleEvent descriptors with descriptor type typeFSS are returned asFSSpec
objects. AppleEvent record descriptors are returned as Python dictionaries, with 4-character string keys and elements recursively unpacked.The optional
formodulename
argument is used by the stub packages generated bygensuitemodule
, and ensures that the OSA classes for object specifiers are looked up in the correct module. This ensures that if, say, the Finder returns an object specifier for a window you get an instance ofFinder.Window
and not a genericaetypes.Window
. The former knows about all the properties and elements a window has in the Finder, while the latter knows no such things.