A.18.11 The Package Containers.Indefinite_Doubly_Linked_Lists
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AI95-00302-03}
The language-defined generic package Containers.Indefinite_Doubly_Linked_Lists
provides private types List and Cursor, and a set of operations for each
type. It provides the same operations as the package Containers.Doubly_Linked_Lists
(see A.18.3), with the difference that the
generic formal Element_Type is indefinite. Static Semantics
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The declaration of the generic library package
Containers.Indefinite_Doubly_Linked_Lists has the
same contents as Containers.Doubly_Linked_Lists except:3/2
- The generic
formal Element_Type is indefinite.
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- The
procedure with the profile:
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procedure Insert (Container : in out List;
Before : in Cursor;
Position : out Cursor;
Count : in Count_Type := 1);
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Discussion: This
procedure is omitted because there is no way to create a default-initialized
object of an indefinite type. We considered having this routine insert
an empty element similar to the empty elements of a vector, but rejected
this possibility because the semantics are fairly complex and very different
from the existing case. That would make it more error-prone to convert
a container from a definite type to an indefinite type; by omitting the
routine completely, any problems will be diagnosed by the compiler.
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- The actual Element
parameter of access subprogram Process of Update_Element may be constrained
even if Element_Type is unconstrained.
Extensions to Ada 95
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AI95-00302-03}
{extensions to Ada 95} The
generic package Containers.Indefinite_Doubly_Linked_Lists is new.
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