Null
A sequential statement that does nothing, normally used within an if or case
statement as an explicit way to take no action under certain conditions. Also,
the value assigned to a guarded signal to mean disconnection, and the value
assigned to an access variable by the procedure DEALLOCATE(Ptr).
Syntax
[Label:] null; {sequential statement}
null {value}
Where
See Sequential Statement and Expression respectively.
Rules
The null statement is not mandatory - it is possible to leave a blank instead.
Example
case Flag is
when TRUE =>
Q := null; -- null value
when FALSE =>
null; -- null statement
end case;
See Also
Case, If, Access, Disconnect
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