    indexing
    	description: "Serialize/Deserialize data from a medium."
    	legal: "See notice at end of class."
    	status: "See notice at end of class."
    	date: "$Date: 2006-01-22 18:25:44 -0800 (Sun, 22 Jan 2006) $"
    	revision: "$Revision: 56675 $"

    class interface
    	SED_MEDIUM_READER_WRITER_1

    create
    	make (a_medium: IO_MEDIUM)
    			-- Initialize current to read or write from `a_medium'.
    		require
    			a_medium_not_void: a_medium /= Void
    		ensure
    			medium_set: medium = a_medium
    			buffer_size_set: buffer_size = default_buffer_size

    	make_with_buffer (a_medium: IO_MEDIUM; a_buffer_size: INTEGER_32)
    			-- Initialize current to read or write from `a_medium' using a buffer of size `a_buffer_size'.
    			-- buffer_size will be overriden during read operation by the value of buffer_size used
    			-- when writing.
    		require
    			a_medium_not_void: a_medium /= Void
    			a_buffer_size_non_negative: a_buffer_size >= 0
    		ensure
    			medium_set: medium = a_medium
    			buffer_size_set: buffer_size = a_buffer_size

    feature -- Access

    	generating_type: STRING_8
    			-- Name of current object's generating type
    			-- (type of which it is a direct instance)
    			-- (from ANY)

    	generator: STRING_8
    			-- Name of current object's generating class
    			-- (base class of the type of which it is a direct instance)
    			-- (from ANY)

    	read_boolean: BOOLEAN
    			-- Read next boolean
    			-- (from SED_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_character_8: CHARACTER_8
    			-- Read next 8-bits character
    			-- (from SED_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_compressed_integer_32: INTEGER_32
    			-- Read next compressed integer_32.
    			-- See read_compressed_natural_32 for more details about encoding.
    			-- (from SED_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_compressed_natural_32: NATURAL_32
    			-- Read next compressed natural_32.
    			-- Depending on first natural_8 value read, it will tell how much more we need to read:
    			-- 1 - Of the form 0xxxxxxx (0x00) for values between 0 and 127
    			-- 2 - Of the form 10xxxxxx (0x80) for values between 128 and 16382 and one more to read.
    			-- 3 - Of the form 110xxxxx (0xC0) for values between 16383 and 2097150 and 2 more to read.
    			-- 4 - Of the form 1110xxxx (0xE0) for values between 2097151 and 268435454 and 3 more to read
    			-- 5 - Otherwise a full natural_32 to read.
    			-- (from SED_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_integer_16: INTEGER_16
    			-- Read next integer_16
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_integer_32: INTEGER_32
    			-- Read next integer_32
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_integer_64: INTEGER_64
    			-- Read next integer_64
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_integer_8: INTEGER_8
    			-- Read next integer_8
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_natural_16: NATURAL_16
    			-- Read next natural_16
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_natural_32: NATURAL_32
    			-- Read next natural_32
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_natural_64: NATURAL_64
    			-- Read next natural_64
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_natural_8: NATURAL_8
    			-- Read next natural_8
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_pointer: POINTER
    			-- Read next pointer
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_real_32: REAL_32
    			-- Read next real_32
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_real_64: REAL_64
    			-- Read next real_64
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_string_8: STRING_8
    			-- Read next 8-bits sequence of character
    			-- (from SED_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading
    		ensure -- from SED_READER_WRITER
    			read_string_8_not_void: Result /= Void

    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 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))

    	is_equal (other: like Current): 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: like Current): 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

    	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

    	is_for_reading: BOOLEAN
    			-- Will current do a read operation?
    			-- (from SED_BINARY_READER_WRITER)

    	is_pointer_value_stored: BOOLEAN
    			-- Is value of a POINTER stored?
    			-- (from SED_READER_WRITER)

    	is_ready_for_reading: BOOLEAN
    			-- Is Current ready for future read operations?
    		require -- from  SED_READER_WRITER
    			True

    	is_ready_for_writing: BOOLEAN
    			-- Is Current ready for future write operations?
    		require -- from  SED_READER_WRITER
    			True

    	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))

    feature -- Element change

    	write_boolean (v: BOOLEAN)
    			-- Write `v'.
    			-- (from SED_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_character_8 (v: CHARACTER_8)
    			-- Write `v'.
    			-- (from SED_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_compressed_integer_32 (v: INTEGER_32)
    			-- Write `v' as a compressed integer_32.
    			-- See write_compressed_natural_32 for details about encoding.
    			-- (from SED_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_compressed_natural_32 (v: NATURAL_32)
    			-- Write `v' as a compressed natural_32.
    			-- Depending on value of `v', it will tell how many natural_8 will
    			-- be written. Below here is the actual encoding where `x' represents
    			-- a meaningful bit for `v' and the last number in parenthesis is the
    			-- marker value in hexadecimal which is added to the value of `v'.
    			-- 1 - For values between 0 and 127, write 0xxxxxxx (0x00).
    			-- 2 - For values between 128 and 16382, write 0x10xxxxxx xxxxxxxx (0xE0).
    			-- 3 - For values between 16383 and 2097150, write 0x110xxxxx xxxxxxxx xxxxxxxx (0xC0).
    			-- 4 - For values between 2097151 and 268435454, write 0x1110xxx xxxxxxxx xxxxxxxx xxxxxxxx (0xE0).
    			-- 5 - Otherwise write `v' as a full natural_32.
    			-- (from SED_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_integer_16 (v: INTEGER_16)
    			-- Write `v'.
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_integer_32 (v: INTEGER_32)
    			-- Write `v'.
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_integer_64 (v: INTEGER_64)
    			-- Write `v'.
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_integer_8 (v: INTEGER_8)
    			-- Write `v'.
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_natural_16 (v: NATURAL_16)
    			-- Write `v'.
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_natural_32 (v: NATURAL_32)
    			-- Write `v'.
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_natural_64 (v: NATURAL_64)
    			-- Write `v'.
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_natural_8 (v: NATURAL_8)
    			-- Write `v'.
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_pointer (v: POINTER)
    			-- Write `v'.
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_real_32 (v: REAL_32)
    			-- Write `v'.
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_real_64 (v: REAL_64)
    			-- Write `v'.
    			-- (from SED_BINARY_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_string_8 (v: STRING_8)
    			-- Write `v'.
    			-- (from SED_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing
    			v_not_void: v /= Void

    feature -- Duplication

    	copy (other: like Current)
    			-- 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: like Current)
    			-- 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: like Current
    			-- New object structure recursively duplicated from Current.
    			-- (from ANY)
    		ensure -- from ANY
    			deep_equal: deep_equal (Current, Result)

    	frozen standard_copy (other: like Current)
    			-- 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: like Current
    			-- 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: like Current
    			-- 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: like Current
    			-- 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 -- Header/Footer

    	read_footer
    			-- Action being executed after finishing to read data.
    			-- (from SED_READER_WRITER)
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading

    	read_header
    			-- Retrieve configuration of how data was stored.
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_reading
    		ensure then
    			buffer_position_reset: buffer_position = 0

    	write_footer
    			-- Store last buffered data.
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing

    	write_header
    			-- Store configuration on how data will be stored.
    		require -- from SED_READER_WRITER
    			is_ready: is_ready_for_writing
    		ensure then
    			buffer_position_reset: buffer_position = 0

    feature -- Output

    	io: STD_FILES
    			-- Handle to standard file setup
    			-- (from ANY)

    	out: STRING_8
    			-- New string containing terse printable representation
    			-- of current object
    			-- Was declared in ANY as synonym of tagged_out.
    			-- (from ANY)

    	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
    			-- Was declared in ANY as synonym of out.
    			-- (from ANY)

    feature -- Platform

    	operating_environment: OPERATING_ENVIRONMENT
    			-- Objects available from the operating system
    			-- (from ANY)

    feature -- Settings

    	set_for_reading
    			-- Set current for reading.
    			-- (from SED_BINARY_READER_WRITER)
    		ensure -- from SED_BINARY_READER_WRITER
    			is_for_reading: is_for_reading

    	set_for_writing
    			-- Set current for writing.
    			-- (from SED_BINARY_READER_WRITER)
    		ensure -- from SED_BINARY_READER_WRITER
    			is_for_writing: not is_for_reading

    	set_is_pointer_value_stored (v: like is_pointer_value_stored)
    			-- Set is_pointer_value_stored with `v'.
    			-- (from SED_READER_WRITER)
    		ensure -- from SED_READER_WRITER
    			is_pointer_value_stored_set: is_pointer_value_stored = v

    invariant
    	medium_not_void: medium /= Void

    		-- from SED_BINARY_READER_WRITER
    	buffer_not_void: buffer /= Void
    	buffer_size_non_negative: buffer_size >= 0
    	buffer_position_non_negative: buffer_position >= 0
    	stored_pointer_bytes_non_negative: stored_pointer_bytes >= 0

    		-- from ANY
    	reflexive_equality: standard_is_equal (Current)
    	reflexive_conformance: conforms_to (Current)

    indexing
    	library: "EiffelBase: Library of reusable components for Eiffel."
    	copyright: "Copyright (c) 1984-2006, Eiffel Software and others"
    	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
    	source: "[
    		Eiffel Software
    		356 Storke Road, Goleta, CA 93117 USA
    		Telephone 805-685-1006, Fax 805-685-6869
    		Website http://www.eiffel.com
    		Customer support http://support.eiffel.com
    	]"

    end -- class SED_MEDIUM_READER_WRITER_1