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POIs it possible to conditionally compile / run code based on a macro OR a variable?
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  1. POIs it possible to conditionally compile / run code based on a macro OR a variable?
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    copied!<p>We have several projects in development sharing the same codebase. Certain pieces of code are only relevant to one or other of those projects.</p> <p>We have a couple of requirements:</p> <p>The first requirement is that we want our final releases not to compile in code from the other projects.</p> <p>One solution (the one we like) is to use the preprocessor to remove that code: (this is what we do in some places).</p> <pre><code>#if defined PROJECT1 { // some code } #endif </code></pre> <p>The second requirement is, that while we are developing, it is helpful to make sure that a change of code still works across all projects, so we would like to compile ALL the project code at once, and be able to switch between projects without a recompile - so in other places in our code, we use a variable to determine the project instead:</p> <pre><code>if (project == 1) { // some code } </code></pre> <p>What I'd like to be able to do is to combine the benefits of both - code which in some situations (let's say determined by a #define REMOVECODE) is not included in the final exe at all, but in other situations (determined by the non-definition of the REMOVECODE define) to include the code in the compiled .exe</p> <p>One more thing - sometimes we have code which exists in a couple of projects, so the solution would need to handle tests like "if project == 1 || project == 2"</p> <p>I'm thinking it would look something like the following (this doesn't work because I don't think you can nest preprocessor directives), but I'm not sure if it is even possible with macros. Maybe there's some kind of template solution?</p> <pre><code>#ifdef REMOVECODE #define BEGINTEST #if #define ENDTEST #endif #define CONDITION1 defined PROJECT1 #else #define BEGINTEST if #define ENDTEST #define CONDITION1 project == 1 #endif BEGINTEST(CONDITION1) { // some code } ENDTEST </code></pre> <p>If anyone can help out, I'd be much obliged.</p>
 

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