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copied!<p><code>clHotlight: TColor = $00FF9933;</code> is not a constant but a typed constant (=static variable), i.e. the compiler reserves a slot in memory for a TColor which will hold the value <code>$00FF9933</code> initially at run time.<br> Because that value can be changed later (with the Assignable Const option ON), it is not a real constant and cannot be accepted by the compiler in <code>clLink = clHotLight;</code> </p> <p><code>clHotlight = TColor($00FF9933);</code> is strictly the same as <code>clHotlight = $00FF9933;</code><br> It is a true constant and the compiler will replace <code>clHotlight</code> by its value <code>$00FF9933</code> wherever it appears in the code. And for <code>clLink</code> as well.</p> <p>Read on this SO question (<a href="https://stackoverflow.com/questions/48934/in-delphi-7-why-can-i-assign-a-value-to-a-const"><strong>In Delphi 7, why can I assign a value to a const?</strong></a>) and all the good answers there...</p> <p><strong>EDIT: about TGUID...</strong><br> The problem is that writing <code>AdministratorGUID: TGUID = '{DE44EEA0-6712-11D4-ADD4-0006295717DA}';</code> is not proper.<br> It is using some <strong>compiler magic</strong> to call <code>StringToGUID</code> behind the scene, allowing the convenience to express the GUID as a string which they are not by nature. They are records. </p> <p>So, trying <code>AdministratorGUID = '{DE44EEA0-6712-11D4-ADD4-0006295717DA}';</code> will not work. That is not a GUID...</p> <p>A workaround is to have <strong>a typed constant</strong> and <strong>variables</strong> pointing to the same memory area using the <strong><code>absolute</code></strong> directive: </p> <pre><code>const AdministratorGUID: TGUID = '{DE44EEA0-6712-11D4-ADD4-0006295717DA}'; var SuperuserGUID: TGUID absolute AdministratorGUID; //alias of AdministratorGUID RootGUID: TGUID absolute AdministratorGUID; //alias of AdministratorGUID </code></pre>

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