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POIs there an intuitive way of checking for flags and states?
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  1. POIs there an intuitive way of checking for flags and states?
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    copied!<p>Couldnt find a relevant answer to my case so i will try explaining my situation:</p> <p>I have the following code:</p> <pre><code>enum Flags { OnlySpaces = 1 &lt;&lt; 0, valComment = 1 &lt;&lt; 1, valCommentBlock = 1 &lt;&lt; 2, valLabelName = 1 &lt;&lt; 3, valVariableName = 1 &lt;&lt; 4, valFunctionName = 1 &lt;&lt; 5, invSyntax = 1 &lt;&lt; 32, fInVarLab = valLabelName|valVariableName, fInIdentifier = valLabelName|valVariableName|valFunctionName, fInCommentBlock = OnlySpaces|valCommentBlock, initState = OnlySpaces|fInIdentifier|valComment, }; int lexStatus = initState; for (int i = 0; sc.More(); sc.Forward(), i++) { if (sc.atLineStart) { if (lexStatus &amp; fInCommentBlock != fInCommentBlock) // Here is the problem sc.SetState(DEFAULT); lexStatus = initState; } ... // More code } </code></pre> <p>My code is for lexing a document and I am trying to do an action only when i am NOT in a comment block. The thing is that the above statement returns exactly the opposite when i am not in a comment...</p> <p>the following statement does the job correctly but seems rather counterintuitive:</p> <p><code>if (lexStatus &amp; fInCommentBlock == fInCommentBlock)</code> </p> <p>So the questions are:</p> <ul> <li>Why? Why is it acting totally the opposite to what i am expecting?</li> </ul> <p>Due to operator precedence <code>if ((lexStatus &amp; fInCommentBlock) != fInCommentBlock)</code> fixes the issue</p> <ul> <li>Am i approaching the correct way? </li> <li>Is there a better way?</li> <li>Is there a way to make sure each flag has a distinct value?</li> </ul> <p>Last question added because for some reason <code>lexStatus &amp; fInCommentBlock</code> because some of the bits ARE set even though i dont set them anywhere in the code...</p> <p>Thanks in advance for your help!</p>
 

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