indexing
	description: "[
		Objects that may be stored and retrieved along with all their dependents.
		This class may be used as ancestor by classes needing its facilities.
	]"
	library: "Free implementation of ELKS library"
	copyright: "Copyright (c) 1986-2008, Eiffel Software and others"
	license: "Eiffel Forum License v2 (see forum.txt)"
	date: "$Date: 2008-05-23 17:24:07 -0700 (Fri, 23 May 2008) $"
	revision: "$Revision: 170 $"

class interface
	STORABLE


create 
	default_create
			-- Process instances of classes with no creation clause.
			-- (Default: do nothing.)
			-- (from ANY)

feature -- Access

	check_instruction: INTEGER_32 is 7
			-- Exception code for violated check
			-- (from EXCEP_CONST)

	class_invariant: INTEGER_32 is 6
			-- Exception code for violated class invariant
			-- (from EXCEP_CONST)

	com_exception: INTEGER_32 is 28
			-- Exception code for a COM error.
			-- (from EXCEP_CONST)

	create_on_deferred: INTEGER_32 is 17
			-- Create on deferred
			-- (from EXCEP_CONST)

	developer_exception: INTEGER_32 is 24
			-- Exception code for developer exception
			-- (from EXCEP_CONST)

	dollar_applied_to_melted_feature: INTEGER_32 is 26
			-- $ applied to melted feature
			-- (from EXCEP_CONST)

	eiffel_runtime_fatal_error: INTEGER_32 is 25
			-- Eiffel run-time fatal error
			-- (from EXCEP_CONST)

	eiffel_runtime_panic: INTEGER_32 is 13
			-- Eiffel run-time panic
			-- (from EXCEP_CONST)

	exception_in_signal_handler: INTEGER_32 is 20
			-- Exception in signal handler
			-- (from EXCEP_CONST)

	exception_manager: EXCEPTION_MANAGER
			-- Exception manager
			-- (from EXCEPTION_MANAGER_FACTORY)
		ensure -- from EXCEPTION_MANAGER_FACTORY
			exception_manager_not_void: Result /= Void

	external_exception: INTEGER_32 is 18
			-- Exception code for operating system error
			-- which does not set the `errno' variable
			-- (Unix-specific)
			-- (from EXCEP_CONST)

	floating_point_exception: INTEGER_32 is 5
			-- Exception code for floating point exception
			-- (from EXCEP_CONST)

	generating_type: STRING_8
			-- Name of current object's generating type
			-- (type of which it is a direct instance)
			-- (from ANY)
		ensure -- from ANY
			generating_type_not_void: Result /= Void
			generating_type_not_empty: not Result.is_empty

	generator: STRING_8
			-- Name of current object's generating class
			-- (base class of the type of which it is a direct instance)
			-- (from ANY)
		ensure -- from ANY
			generator_not_void: Result /= Void
			generator_not_empty: not Result.is_empty

	incorrect_inspect_value: INTEGER_32 is 9
			-- Exception code for inspect value which is not one
			-- of the inspect constants, if there is no Else_part
			-- (from EXCEP_CONST)

	io_exception: INTEGER_32 is 21
			-- Exception code for I/O error
			-- (from EXCEP_CONST)

	loop_invariant: INTEGER_32 is 11
			-- Exception code for violated loop invariant
			-- (from EXCEP_CONST)

	loop_variant: INTEGER_32 is 10
			-- Exception code for non-decreased loop variant
			-- (from EXCEP_CONST)

	no_more_memory: INTEGER_32 is 2
			-- Exception code for failed memory allocation
			-- (from EXCEP_CONST)

	number_of_codes: INTEGER_32 is 31
			-- How many codes are there to represent exceptions?
			-- (from EXCEP_CONST)

	old_exception: INTEGER_32 is 30
			-- Old exception code.
			-- (from EXCEP_CONST)

	operating_system_exception: INTEGER_32 is 22
			-- Exception code for operating system error
			-- which sets the `errno' variable
			-- (Unix-specific)
			-- (from EXCEP_CONST)

	out_of_memory: INTEGER_32 is 15
			-- Out of memory (cannot be ignored)
			-- (from EXCEP_CONST)

	postcondition: INTEGER_32 is 4
			-- Exception code for violated postcondition
			-- (from EXCEP_CONST)

	precondition: INTEGER_32 is 3
			-- Exception code for violated precondition
			-- (from EXCEP_CONST)

	rescue_exception: INTEGER_32 is 14
			-- Exception code for exception in rescue clause
			-- (from EXCEP_CONST)

	resumption_failed: INTEGER_32 is 16
			-- Resumption failed (retry did not succeed)
			-- (from EXCEP_CONST)

	retrieve_by_name (file_name: STRING_8): ?ANY
			-- Retrieve object structure, from external
			-- representation previously stored in a file
			-- called `file_name'.
			-- To access resulting object under correct type,
			-- use assignment attempt.
			-- Will raise an exception (code Retrieve_exception)
			-- if file content is not a stored Eiffel structure.
			-- Will return Void if the file does not exist or
			-- is not readable.
		require
			file_name_exists: file_name /= Void
			file_name_meaningful: not file_name.is_empty

	retrieve_exception: INTEGER_32 is 23
			-- Exception code for retrieval error
			-- may be raised by retrieved in `IO_MEDIUM'.
			-- (from EXCEP_CONST)

	retrieved (medium: IO_MEDIUM): ANY
			-- Retrieved object structure, from external
			-- representation previously stored in `medium'.
			-- To access resulting object under correct type,
			-- use assignment attempt.
			-- Will raise an exception (code Retrieve_exception)
			-- if medium content is not a stored Eiffel structure.
		require
			medium_not_void: medium /= Void
			medium_exists: medium.exists
			medium_is_open_read: medium.is_open_read
			medium_supports_storable: medium.support_storable
		ensure
			result_exists: Result /= Void

	routine_failure: INTEGER_32 is 8
			-- Exception code for failed routine
			-- (from EXCEP_CONST)

	runtime_check_exception: INTEGER_32 is 29
			-- Exception code for runtime check being violated.
			-- (from EXCEP_CONST)

	runtime_io_exception: INTEGER_32 is 27
			-- Exception code for I/O error raised by runtime functions
			-- such as store/retrieve, file access...
			-- (from EXCEP_CONST)

	serialization_exception: INTEGER_32 is 31
			-- Serialization exception code.
			-- (from EXCEP_CONST)

	signal_exception: INTEGER_32 is 12
			-- Exception code for operating system signal
			-- (from EXCEP_CONST)

	valid_code (c: INTEGER_32): BOOLEAN
			-- Is `c' a valid code to represent some kind of exceptions?
			-- (from EXCEP_CONST)

	void_assigned_to_expanded: INTEGER_32 is 19
			-- Exception code for assignment of void value
			-- to expanded entity
			-- (from EXCEP_CONST)

	void_call_target: INTEGER_32 is 1
			-- Exception code for feature applied to void reference
			-- (from EXCEP_CONST)
	
feature -- Comparison

	frozen deep_equal (some: ?ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void
			-- or attached to isomorphic object structures?
			-- (from ANY)
		ensure -- from ANY
			shallow_implies_deep: standard_equal (some, other) implies Result
			both_or_none_void: (some = Void) implies (Result = (other = Void))
			same_type: (Result and (some /= Void)) implies (other /= Void and then some.same_type (other))
			symmetric: Result implies deep_equal (other, some)

	frozen equal (some: ?ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void or attached
			-- to objects considered equal?
			-- (from ANY)
		ensure -- from ANY
			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.is_equal (other))

	frozen is_deep_equal (other: STORABLE): BOOLEAN
			-- Are `Current' and `other' attached to isomorphic object structures?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			shallow_implies_deep: standard_is_equal (other) implies Result
			same_type: Result implies same_type (other)
			symmetric: Result implies other.is_deep_equal (Current)

	is_equal (other: STORABLE): BOOLEAN
			-- Is `other' attached to an object considered
			-- equal to current object?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			symmetric: Result implies other.is_equal (Current)
			consistent: standard_is_equal (other) implies Result

	frozen standard_equal (some: ?ANY; other: like arg #1): BOOLEAN
			-- Are `some' and `other' either both void or attached to
			-- field-by-field identical objects of the same type?
			-- Always uses default object comparison criterion.
			-- (from ANY)
		ensure -- from ANY
			definition: Result = (some = Void and other = Void) or else ((some /= Void and other /= Void) and then some.standard_is_equal (other))

	frozen standard_is_equal (other: STORABLE): BOOLEAN
			-- Is `other' attached to an object of the same type
			-- as current object, and field-by-field identical to it?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			same_type: Result implies same_type (other)
			symmetric: Result implies other.standard_is_equal (Current)
	
feature -- Status report

	assertion_violation: BOOLEAN
			-- Is last exception originally due to a violated
			-- assertion or non-decreasing variant?
			-- (from EXCEPTIONS)

	class_name: ?STRING_8
			-- Name of the class that includes the recipient
			-- of original form of last exception
			-- (from EXCEPTIONS)

	conforms_to (other: ANY): BOOLEAN
			-- Does type of current object conform to type
			-- of `other' (as per Eiffel: The Language, chapter 13)?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void

	developer_exception_name: ?STRING_8
			-- Name of last developer-raised exception
			-- (from EXCEPTIONS)
		require -- from EXCEPTIONS
			applicable: is_developer_exception

	exception: INTEGER_32
			-- Code of last exception that occurred
			-- (from EXCEPTIONS)

	exception_trace: ?STRING_8
			-- String representation of the exception trace
			-- (from EXCEPTIONS)

	is_developer_exception: BOOLEAN
			-- Is the last exception originally due to
			-- a developer exception?
			-- (from EXCEPTIONS)

	is_developer_exception_of_name (name: STRING_8): BOOLEAN
			-- Is the last exception originally due to a developer
			-- exception of name `name'?
			-- (from EXCEPTIONS)

	is_signal: BOOLEAN
			-- Is last exception originally due to an external
			-- event (operating system signal)?
			-- (from EXCEPTIONS)

	is_system_exception: BOOLEAN
			-- Is last exception originally due to an
			-- external event (operating system error)?
			-- (from EXCEPTIONS)

	meaning (except: INTEGER_32): ?STRING_8
			-- A message in English describing what `except' is
			-- (from EXCEPTIONS)

	original_class_name: ?STRING_8
			-- Name of the class that includes the recipient
			-- of original form of last exception
			-- (from EXCEPTIONS)

	original_exception: INTEGER_32
			-- Original code of last exception that triggered
			-- current exception
			-- (from EXCEPTIONS)

	original_recipient_name: ?STRING_8
			-- Name of the routine whose execution was
			-- interrupted by original form of last exception
			-- (from EXCEPTIONS)

	original_tag_name: ?STRING_8
			-- Assertion tag for original form of last
			-- assertion violation.
			-- (from EXCEPTIONS)

	recipient_name: ?STRING_8
			-- Name of the routine whose execution was
			-- interrupted by last exception
			-- (from EXCEPTIONS)

	same_type (other: ANY): BOOLEAN
			-- Is type of current object identical to type of `other'?
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			definition: Result = (conforms_to (other) and other.conforms_to (Current))

	tag_name: ?STRING_8
			-- Tag of last violated assertion clause
			-- (from EXCEPTIONS)
	
feature -- Status setting

	catch (code: INTEGER_32)
			-- Make sure that any exception of code `code' will be
			-- caught. This is the default.
			-- (from EXCEPTIONS)

	die (code: INTEGER_32)
			-- Terminate execution with exit status `code',
			-- without triggering an exception.
			-- (from EXCEPTIONS)

	ignore (code: INTEGER_32)
			-- Make sure that any exception of code `code' will be
			-- ignored. This is not the default.
			-- (from EXCEPTIONS)

	message_on_failure
			-- Print an exception history table
			-- in case of failure.
			-- This is the default.
			-- (from EXCEPTIONS)

	no_message_on_failure
			-- Do not print an exception history table
			-- in case of failure.
			-- (from EXCEPTIONS)

	raise (name: STRING_8)
			-- Raise a developer exception of name `name'.
			-- (from EXCEPTIONS)

	raise_retrieval_exception (name: STRING_8)
			-- Raise a retrieval exception of name `name'.
			-- (from EXCEPTIONS)
	
feature -- Element change

	basic_store (medium: IO_MEDIUM)
			-- Produce on `medium' an external representation of the
			-- entire object structure reachable from current object.
			-- Retrievable within current system only.
		require
			medium_not_void: medium /= Void
			medium_exists: medium.exists
			medium_is_open_write: medium.is_open_write
			medium_supports_storable: medium.support_storable

	general_store (medium: IO_MEDIUM)
			-- Produce on `medium' an external representation of the
			-- entire object structure reachable from current object.
			-- Retrievable from other systems for same platform
			-- (machine architecture).
		require
			medium_not_void: medium /= Void
			medium_exists: medium.exists
			medium_is_open_write: medium.is_open_write
			medium_supports_storable: medium.support_storable

	independent_store (medium: IO_MEDIUM)
			-- Produce on `medium' an external representation of the
			-- entire object structure reachable from current object.
			-- Retrievable from other systems for the same or other
			-- platform (machine architecture).
		require
			medium_not_void: medium /= Void
			medium_exists: medium.exists
			medium_is_open_write: medium.is_open_write
			medium_supports_storable: medium.support_storable

	store_by_name (file_name: STRING_8)
			-- Produce on file called `file_name' an external
			-- representation of the entire object structure
			-- reachable from current object.
			-- Retrievable from other systems for same platform
			-- (machine architecture).
		require
			file_name_not_void: file_name /= Void
			file_name_meaningful: not file_name.is_empty
	
feature -- Duplication

	copy (other: STORABLE)
			-- Update current object using fields of object attached
			-- to `other', so as to yield equal objects.
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
			type_identity: same_type (other)
		ensure -- from ANY
			is_equal: is_equal (other)

	frozen deep_copy (other: STORABLE)
			-- Effect equivalent to that of:
			--		copy (`other' . deep_twin)
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
		ensure -- from ANY
			deep_equal: deep_equal (Current, other)

	frozen deep_twin: STORABLE
			-- New object structure recursively duplicated from Current.
			-- (from ANY)
		ensure -- from ANY
			deep_twin_not_void: Result /= Void
			deep_equal: deep_equal (Current, Result)

	frozen standard_copy (other: STORABLE)
			-- Copy every field of `other' onto corresponding field
			-- of current object.
			-- (from ANY)
		require -- from ANY
			other_not_void: other /= Void
			type_identity: same_type (other)
		ensure -- from ANY
			is_standard_equal: standard_is_equal (other)

	frozen standard_twin: STORABLE
			-- New object field-by-field identical to `other'.
			-- Always uses default copying semantics.
			-- (from ANY)
		ensure -- from ANY
			standard_twin_not_void: Result /= Void
			equal: standard_equal (Result, Current)

	frozen twin: STORABLE
			-- New object equal to `Current'
			-- twin calls copy; to change copying/twining semantics, redefine copy.
			-- (from ANY)
		ensure -- from ANY
			twin_not_void: Result /= Void
			is_equal: Result.is_equal (Current)
	
feature -- Basic operations

	frozen default: ?STORABLE
			-- Default value of object's type
			-- (from ANY)

	frozen default_pointer: POINTER
			-- Default value of type `POINTER'
			-- (Avoid the need to write `p'.default for
			-- some `p' of type `POINTER'.)
			-- (from ANY)

	default_rescue
			-- Process exception for routines with no Rescue clause.
			-- (Default: do nothing.)
			-- (from ANY)

	frozen do_nothing
			-- Execute a null action.
			-- (from ANY)
	
feature -- Output

	io: STD_FILES
			-- Handle to standard file setup
			-- (from ANY)
		ensure -- from ANY
			io_not_void: Result /= Void

	out: STRING_8
			-- New string containing terse printable representation
			-- of current object
			-- (from ANY)
		ensure -- from ANY
			out_not_void: Result /= Void

	print (some: ?ANY)
			-- Write terse external representation of `some'
			-- on standard output.
			-- (from ANY)

	frozen tagged_out: STRING_8
			-- New string containing terse printable representation
			-- of current object
			-- (from ANY)
		ensure -- from ANY
			tagged_out_not_void: Result /= Void
	
feature -- Platform

	operating_environment: OPERATING_ENVIRONMENT
			-- Objects available from the operating system
			-- (from ANY)
		ensure -- from ANY
			operating_environment_not_void: Result /= Void
	
feature -- Setting

	set_discard_pointers (v: BOOLEAN)
			-- If `v' it will discard POINTER values and replace them by
			-- the default_pointer pointer. Otherwise it keeps the original value.

	set_new_independent_format (v: BOOLEAN)
			-- If `v' it will use ISE Eiffel 5.0 storable format for
			-- storing.

	set_new_recoverable_format (v: BOOLEAN)
			-- If `v' it will use ISE Eiffel 5.3 storable format for
			-- storing with ability to recover when there is a type mismatch.
	
invariant
		-- from ANY
	reflexive_equality: standard_is_equal (Current)
	reflexive_conformance: conforms_to (Current)

end -- class STORABLE