preprocessor

问题 In my project there's a file enclosed in an ifdef preprocessor directive #ifdef SOME_SYMBOL ... entire file ... #endif SOME_SYMBOL is defined by another file that's compiled before this one, and the code works as expected, but the static analyzer isn't aware of this symbol and so it treats SOME_SYMBOL is undefined. The entire file has no syntax highlighting and some of the analysis is just skipped (e.g. syntax error highlighting). Is there a way to tell the analyzer to treat this symbol as

问题 JavaScript toolkits like jQuery are all about callback functions, and those callbacks are frequently defined anonymously. Example: Some webpage shows a list of messages in a table. To update this table, it might first ask the server for a list of all current messages (as IDs), then retrieve the content for the yet-unknown message IDs: function fnUpdateMessages() { $.ajax({ type: 'POST', data: { action: 'get_message_ids' }, success: function(sData) { var aMessageIds = sData.split(/,/); var

问题 I have a configuration that I'd like to dynamically control a preprocessor defined value through an environment variable. Is this possible? if it is how do I set in the preprocessor define table that I want to set the value based on the environment variable? 回答1: In the "Build Settings" of a target of your project, you can add something like that to the "Preprocessor Macros" field: DEV_USERNAME="${USER}" Of course, the USER variable can be replaced by any environment variable available to

问题 I've been a Java and VB.Net programmer for about 4 years and a C# programmer for about 6 months. I've also used a bunch of dynamic languages like Perl, Python, PHP, and JavaScript. I've never had a need for a preprocessor. My question is: why do you see such extensive use of preprocessors in C, C++, and Objective-C but rarely (or never) see it in languages like Java, C#, or Scala? 回答1: I don't know Objective-C, so my answer will be about contrasting the use of the preprocessor in C and C++.

问题 I have a Swift demo project that comes bundled with my framework. I want to ensure that the Swift code in the demo compiles successfully with both Xcode 6 (Swift 1.2) and Xcode 7 (Swift 2.0) without user intervention . Since there's only marginal preprocessor support in Swift, how can I determine at compile-time which version of Swift or Xcode is being used to compile the code? Now, here's the important detail: It has to work automatically! Open the project in Xcode 6 -> compiles the Swift 1

问题 I've been doing a lot of cross-compiling of different libraries for iOS and until iOS5 there was no problem. Ok, apparently my problem is, that the iOS5 SDK does not include the GNU gcc compiler any more. Only llvm and clang are available. My problem is, that I cannot finish to run the 'configure' script of any library any more. It always fails with: configure: error: C preprocessor "/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc" fails sanity check gcc only is a symbolic link

问题 I want to theme the template for edit or add a node for a specific content type. For example, to theme all the content type forms I use the file page-node-{add|edit}.tpl.php (depending what I need to do add or edit). But I didn't found the template name for a custom node type, for example Products. I need to theme only for Products, but not for the other content types. I've tried with page-node-edit-product.tpl.php and page-node-product-edit.tpl.php but no luck. 回答1: Hmm. There may be a

问题 I want to theme the template for edit or add a node for a specific content type. For example, to theme all the content type forms I use the file page-node-{add|edit}.tpl.php (depending what I need to do add or edit). But I didn't found the template name for a custom node type, for example Products. I need to theme only for Products, but not for the other content types. I've tried with page-node-edit-product.tpl.php and page-node-product-edit.tpl.php but no luck. 回答1: Hmm. There may be a

问题 I have a header file that is included by both a native cpp file and a managed cpp file(compiled with /clr). It includes only native types, but I want to specify that the native types are visible outside the assembly (see http://msdn.microsoft.com/en-us/library/4dffacbw(VS.80).aspx). Essentially, I want: public class NativeClass // The public makes this visible outside the assembly. { }; If I include this code from a native cpp, I get the following error: error C3381: 'NativeClass' : assembly

问题 I'm using the PorterStemmer Python Port The Porter stemming algorithm (or ‘Porter stemmer’) is a process for removing the commoner morphological and inflexional endings from words in English. Its main use is as part of a term normalisation process that is usually done when setting up Information Retrieval systems. For the following.. The other thing you need to do is reduce each word to its stem. For example, the words sing , sings , singing all have the same stem, which is sing . There is a