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Assigned function

In unit System

Check if a pointer is valid.

Declaration

pascal
function Assigned(P: Pointer): Boolean

Description

Assigned returns True if P is non-nil and returns False of P is nil. The main use of Assigned is that Procedural variables, method variables and class-type variables also can be passed to Assigned.

Errors

None

See also

Example: ex96

pascal
Program Example96;

{ Program to demonstrate the Assigned function. }

Var P : Pointer;

begin
  If Not Assigned(P) then
    Writeln ('Pointer is initially NIL');
  P:=@P;
  If Not Assigned(P) then
    Writeln('Internal inconsistency')
  else
    Writeln('All is well in FPC')
end.

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.