This class represents an external function called from Smalltalk. Instances of ExternalFunction can be created if the address/parameters of the function are known by some other means than loading from a shared library or compiling the appropriate primitive specification.

Instance variables:
flags <Integer> a set of flags encoding the calling convention
args <Array of: ExternalType> the parameters of the function

Implementation notes:

The arguments consist of an array with the first element defining the return type, the remaining arguments defining the parameters of the call.

	initialize-release
	initialize

	invoking
	invoke invokeWith: invokeWith:with: invokeWith:with:with: invokeWith:with:with:with: invokeWith:with:with:with:with: invokeWith:with:with:with:with:with: invokeWithArguments:

	printing
	callingConventionString printOn:

	compiler support
	atomicTypeNamed: callingConventionFor: forceTypeNamed: isValidType: structTypeNamed:

	constants
	callTypeAPI callTypeCDecl

	error handling
	errorMessageFor: externalCallFailed getLastError

	accessing	top
	argTypes
	flags
	module
	name Answer a name for the receiver. This is used generically in the title of certain inspectors, such as the referred-to inspector, and specificially by various subsystems. By default, we let the object just print itself out..

	initialize-release	top
	initialize Initialize the receiver

	invoking	top
	invoke
	invokeWith:
	invokeWith:with:
	invokeWith:with:with:
	invokeWith:with:with:with:
	invokeWith:with:with:with:with:
	invokeWith:with:with:with:with:with:
	invokeWithArguments: Manually invoke the receiver, representing an external function.

	printing	top
	callingConventionString
	printOn: Append to the argument, aStream, a sequence of characters that identifies the receiver.

	class initialization	top
	initialize ExternalFunction initialize
	initializeCallingConventions ExternalFunction initializeCallingConventions
	initializeErrorConstants ExternalFunction initializeErrorConstants

	compiler support	top
	atomicTypeNamed:
	callingConventionFor: Return the constant describing the calling convention for the given string specification or nil if unknown.
	forceTypeNamed:
	isValidType:
	structTypeNamed:

	constants	top
	callTypeAPI
	callTypeCDecl

	error handling	top
	errorMessageFor: Return the error message for the given error code from the foreign function interface
	externalCallFailed Raise an error after a failed call to an external function
	getLastError Return the last error from an external call. Only valid immediately after the external call failed.