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3.7.2 Operations of Discriminated Types
1
If a discriminated type has default_expressions
for its discriminants, then unconstrained variables of the type are permitted,
and the discriminants of such a variable can be changed by assignment
to the variable. For a formal parameter of such a type, an attribute
is provided to determine whether the corresponding actual parameter is
constrained or unconstrained.
Static Semantics
2
For a prefix
A that is of a discriminated type (after any implicit dereference), the
following attribute is defined:
3
- A'Constrained
-
Yields the value True if A denotes
a constant, a value, or a constrained variable, and False otherwise.
Erroneous Execution
4
The execution of a construct
is erroneous if the construct has a constituent that is a
name
denoting a subcomponent that depends on discriminants, and the value
of any of these discriminants is changed by this execution between evaluating
the
name and the last use (within
this execution) of the subcomponent denoted by the
name.
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