conditional-compilation

问题 i can add a define to a WinForms project through the Project Properties : How do i add a define to an ASP.net solution? Update : Here's what Visual Studio 2010 looks like when working in an ASP.net solution: 回答1: Solution Explorer > WebApplicationProject (Name of your Web Application) > Properties > Build: 回答2: Have you tried using the compilerOptions attribute of the compiler v element in web.config ? Like so: <system.codedom> <compilers> <compiler language="c#;cs;csharp" extension=".cs"

问题 I coded a little logging-lib for myself, and it accepts two forms calling. The one likes a normal function calling, the other likes a std::ostream << operator output. And then I defined a few of Macros respectively for every log-levels as following: #ifdef DEBUG #define LOG_DEBUG( strLogBody ) appendLog( leon_log::LogLevel_e::ellDebug, std::string( __func__ ) + "()," + ( strLogBody ) ) #define LOG_INFOR( strLogBody ) appendLog( leon_log::LogLevel_e::ellInfor, std::string( __func__ ) + "()," +

问题 I have come across some example code that goes like this: #ifdef WIN32 ... #elif WIN64 ... #endif In an #ifdef block, is it actually legal to use #elif to mean #elif defined ? 回答1: No, it shouldn't be. That's not to say that some obscure C compiler wouldn't accept it as such, but it isn't part of the C standard. Normally, for something like this you would use either #elifdef FOO (which I've never actually seen in production code) or #elif defined(FOO) (like you mentioned). This code appears

问题 I have some helper methods marked with [Conditional("XXX")] . The intent is to make the methods conditionally compile when only the XXX conditional compilation symbol is present. We're using this for debugging and tracing functionality and it works quite well. During my research on how the conditional compilation works, I found several sources stating methods tagged with the Conditional attribute will be placed in the IL but calls to the methods will not be executed. How does code get

问题 Consider the following class, with the inner struct Y being used as a type, eg. in templates, later on: template<int I> class X{ template<class T1> struct Y{}; template<class T1, class T2> struct Y{}; }; Now, this example will obviously not compile, with the error that the second X<I>::Y has already been defined or that it has too many template parameters. I'd like to resolve that without (extra) partial specialization, since the int I parameter isn't the only one and the position of it can

问题 I have a function that is capable of being implemented as a const : #![feature(const_fn)] // My crate would have: const fn very_complicated_logic(a: u8, b: u8) -> u8 { a * b } // The caller would have: const ANSWER: u8 = very_complicated_logic(1, 2); fn main() {} I'd like to continue to support stable Rust where it's not possible to define such functions. These stable consumers would not be able to use the function in a const or static , but should be able to use the function in other

问题 Imagine I have two .hpp files: #ifndef _DEF_FILE_1_ #define _DEF_FILE_1_ inline void some_function_1(){ /*do stuff*/ } #endif and #ifndef _DEF_FILE_2_ #define _DEF_FILE_2_ #ifdef _DEF_FILE_1_ inline void some_function_2(){ /*do stuff using some_function_1()*/ } #else inline void some_function_2(){ /*do the same stuff without using some_function_1()*/ } #endif #endif My problem arises when I don't know in which order the files are included, e.g: in the main.cpp i can have something like :

问题 Can you use macros defined in static libraries? I have my own debug macro called TWDEBUG that I use in a static library I create for sharing. If I import the static library to my new project and use it, the compiler does not seem to recognize it. I did set up preprocessor macros to TWDEBUG and Other C flags and Other C++ flags to -TWDEBUG , but when I ran the code the ifdef macro doesn't get executed. 回答1: Macros are evaluated at compile-time. So their values are frozen when you build the

问题 for our project we always used one source file for both platforms: iOS and OS X. Right now I am migrating to swift. Unfortunately there is some files which need import Cocoa and on iOS import UIKit previously we did #ifdef __MAC_OS_X_VERSION_MAX_ALLOWED #import <Cocoa/Cocoa.h> #else #import <UIKit/UIKit.h> #endif Do you know how this can be done in swift? I don't like to write each class twice just because there is no macros anymore. Thanks in advance Jack 回答1: Use: #if os(OSX) import Cocoa

问题 I'm building a windows service application which has a configuration to compile it as a basic windows application. The main project file for the exe includes conditionals which determine whether the project is being compiled as a service application or as a windows forms application. The problem is, when I do something which makes the project code change, the code gets destroyed and broken. For example, a line which says Application.Initialize; becomes AppliApplication.Initialize; and the