[fpc-pascal] Checking assignment compatibility

[Mark Morgan Lloyd]

Simulating a C-style conditional, I can do this

function tf(const q: qword; const qt, qf: TObject): TObject; inline;

begin
   Assert(TypeOf(qt) = TypeOf(result));

which- as I understand it- checks that the types are strictly the same. 
How do I relax this to only ensure that the parameter is 
assignment-compatible with the result? I presume that it's an  is 
relationship but so far the syntax eludes me.

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

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