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5.16 Class STORABLE

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."

class interface

feature -- Access

retrieved (file: FILE): STORABLE

-- Retrieved object structure, from external

-- representation previously stored in file.

-- To access resulting object under correct type,

-- use assignment attempt.

-- Will raise an exception (code Retrieve_exception)

-- if file content is not a STORABLE structure.

require

file_not_void: file /= Void;

file_exists: file.exists;

file_is_open_read: file.is_open_read

file_not_plain_text: not file.is_plain_text

ensure

result_exists: Result /= Void

feature -- Element change

basic_store (file: FILE)

-- Produce on file an external representation of the

-- entire object structure reachable from current object.

-- Retrievable within current system only.

require

file_not_void: file /= Void;

file_exists: file.exists;

file_is_open_write: file.is_open_write;

file_not_plain_text: not file.is_plain_text

general_store (file: FILE)

-- Produce on file an external representation of the

-- entire object structure reachable from current object.

-- Retrievable from other systems for same platform

-- (machine architecture).

require

file_not_void: file /= Void;

file_exists: file.exists;

file_is_open_write: file.is_open_write;

file_not_plain_text: not file.is_plain_text

independent_store (file: FILE)

-- Produce on file an external representation of the

-- entire object structure reachable from current object.

-- Retrievable from other systems for the same or other

-- platforms (machine architectures).

require

file_not_void: file /= Void;

file_exists: file.exists;

file_is_open_write: file.is_open_write;

file_not_plain_text: not file.is_plain_text

end