- (1)
- A remote types library unit supports the definition of types intended for
use in communication between active partitions.
- (2)
- The form of a pragma Remote_Types is as follows:
(3)
pragma Remote_Types[(library_unit_name)];
Legality Rules
- (4)
- A remote types library unit is a library unit to which the pragma Remote_Types applies. The following restrictions apply to the declaration of such a
library unit:
- (5)
- it shall be preelaborable;
- (6)
- it shall depend semantically only on declared pure, shared
passive, or other remote types library units;
- (7)
- it shall not contain the declaration of any variable within the
visible part of the library unit;
- (8)
- if the full view of a type declared in the visible part of the
library unit has a part that is of a non-remote access type, then
that access type, or the type of some part that includes the
access type subcomponent, shall have user-specified Read and
Write attributes.
- (9)
- An access type declared in the visible part of a remote types or remote
call interface library unit is called a remote access type. Such a type
shall be either an access-to-subprogram type or a general access type that
designates a class-wide limited private type.
- (10)
- The following restrictions apply to the use of a remote
access-to-subprogram type:
- (11)
- A value of a remote access-to-subprogram type shall be converted
only to another (subtype-conformant) remote access-to-subprogram
type;
- (12)
- The prefix of an Access attribute_reference that yields a value
of a remote access-to-subprogram type shall statically denote a
(subtype-conformant) remote subprogram.
- (13)
- The following restrictions apply to the use of a remote
access-to-class-wide type:
- (14)
- The primitive subprograms of the corresponding specific limited
private type shall only have access parameters if they are
controlling formal parameters; the types of all the
non-controlling formal parameters shall have Read and Write
attributes.
- (15)
- A value of a remote access-to-class-wide type shall be explicitly
converted only to another remote access-to-class-wide type;
- (16)
- A value of a remote access-to-class-wide type shall be dereferenced
(or implicitly converted to an anonymous access type) only as part of
a dispatching call where the value designates a controlling operand of
the call (see E.4, ``Remote Subprogram Calls'');
- (17)
- The Storage_Pool and Storage_Size attributes are not defined for
remote access-to-class-wide types; the expected type for an
allocator shall not be a remote access-to-class-wide type; a
remote access-to-class-wide type shall not be an actual parameter
for a generic formal access type;
-
- (18)
(5) A remote types library unit need not be pure, and the types it defines
may include levels of indirection implemented by using access types. User-specified
Read and Write attributes (see 13.13.2) provide
for sending values of such a type between active partitions, with Write
marshalling the representation, and Read unmarshalling any levels of indirection.
-- Email comments, additions, corrections, gripes, kudos, etc. to:
Magnus Kempe -- Magnus.Kempe@di.epfl.ch
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