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    <p>You have two circular reference issues. Firstly you are declaring two units which each refer to the other in the interface section. That can be solved a variety of ways. For now For now I am going to ignore that issue and focus on the other circular reference problem. In order to do so I'm going to assume all code appears in the same unit.</p> <p>The more pressing circular reference problem is that <code>TIns</code> refers to <code>TExtract</code> and vice versa. In order to break this particular circularity you would need to introduce a forward reference, just as is commonly done with classes. But it turns out that forward references cannot be made for <code>record</code> types.</p> <p>Whilst forward references are possible for class types, there is a fundamental difference between class types and record types. Record types are value types and class types are reference types. The current implementation of the Delphi compiler does not support forward references for value types.</p> <p>The solution to your problem is to move the operators that refer to both types to whichever record is declared last. For example:</p> <pre><code>TIns = record private type TInsArray = array [1..90] of Boolean; var FInsArray: TInsArray; end; TExtract = record private type TExtractEnum = 1 .. 90; var FExtractEnum: TExtractEnum; public class operator Implicit(const Value: TExtract): TIns; class operator Implicit(const Value: TIns): TExtract; class operator Implicit(const Value: Integer): TExtract; class operator Implicit(const Value: TExtract): Integer; class operator In(A: TExtract; B: TIns) : Boolean; end; </code></pre> <p>If you wish to retain two separate units then do it like this:</p> <ol> <li>Put <code>TIns</code> in the unit <code>_TIns</code>.</li> <li>Do <strong>not</strong> use <code>_TExtract</code> from <code>_TIns</code>. </li> <li>Put <code>TExtract</code> in the unit <code>_TExtract</code>.</li> <li>Use <code>_TIns</code> from the interface section of <code>_TExtract</code>. </li> </ol> <p>Like this:</p> <pre><code>unit _TIns; interface type TIns = record private type TInsArray = array [1..90] of Boolean; var FInsArray: TInsArray; end; implementation end. </code></pre> <p>&nbsp;</p> <pre><code>unit _TExtract; interface uses _TIns; type TExtract = record private type TExtractEnum = 1 .. 90; var FExtractEnum: TExtractEnum; public class operator Implicit(const Value: TExtract): TIns; class operator Implicit(const Value: TIns): TExtract; class operator Implicit(const Value: Integer): TExtract; class operator Implicit(const Value: TExtract): Integer; class operator In(A: TExtract; B: TIns) : Boolean; end; implementation // Code end. </code></pre>
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    1. USDavid Heffernan
    1. USDavid Heffernan
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    1. COUnderstood, then i should copy code of _TExtract implemantation in _TIns implementation for solve it and not call _TExtract. Ok, thanks very much.
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    2. COI've remembered what the solution to the problem is and have added it to the answer.
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    3. COThe problem is that both operator call other. So i need to do it for both without so call unit, correct?
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