swift macros

Jason Clark This article assumes that you are familiar with. NET and C # Download the code for this article: Plug-ins.exe (135KB) Overview Most user applications benefit from the ability to be extended by other developers. Extending an existing application that a user is already familiar with and training for is often simpler and more effective than developing from scratch. Therefore, scalability makes your application more appealing. You can make your application extensible by supporting featur

Problem: There is a requirement in work: you need to make some judgments and substitutions in LD script using macro definitions like C-Define.Experiment:1: Theoretically *.c can be used, whether GCC/LD also support the direct use of the macro in LD script, the result:Arm-linux-ld:xxx.lds:2: Ignoring invalid character ' # ' in Expressionarm-linux-ld:xxx.lds:2: syntax errorPeople say Shui, it seems that LD and GCC are not face ah. Here is the cross-compilation of the ld,x86 is the same conclusion,

Pre-processing macros in C + +An example of a preprocessing macro:# define PRINT (Str,var) coutThe arguments in parentheses following the macro name are replaced by all code that follows the closing parenthesis. Whenever the macro is called, the preprocessor removes the name print and replaces the code, so the compiler does not report any error messages when using the macro name, and it does not do any type checking on the parameters.Another example:#

The following information is excerpted from the documentation for standard C + +.If these macros are added to the program's log, it will provide a good help for the developer in analyzing the problem.standard C + + version 1998The following macro names shall is defined by the implementation:__line__ the line number of the current source line (a decimal constant).__file__ the presumed name of the source FILE (a character string literal).__date__ the DA

:#ifdef _cplusplus#define Extern_c EXTERN "C"#else#define Extern_c EXTERN#endif#ifdef _cplusplusextern "C" {#endifExtern_c int func (int a, int b);#ifdef _cplusplus}#endif5, MFC provides some macros, you can use Afx_ext_class to replace __declspec (DLLexport), and modify the class name, thereby exporting the class, afx_api_export to modify the function, Afx_data_export to modify the variableAfx_class_import:__declspec (DLLexport)Afx_api_import:__decls

Macros inside parameters without parentheses error-prone, when used as far as possible parenthesesProgram 1:#include #define sqare(X) x*xint Main (){int n = ten;int m= Sqare (n);printf ("m=%d\n", m);return 0;}Results:m=100Please press any key to continue ...Analysis: There seems to be no problem, see the following two examplesProgram 2:#include #define sqare(X) x*xint Main (){int m = Sqare (1 + 3); //1+3*1+3=7printf ("m=%d\n", m);return 0;}Results

the value of the list on the varargs variable. Kwargs is the same as varargs, but only for the keyword parameter. All unused keyword parameters are stored in this special variable. Caller if a macro is called by a call tag, the caller is stored in the variable as a callable macro. Macros can also expose certain internal details. The following macro object properties are available: The name of the name macro. {{Input.name}} will print input. Arguments

Calculation of bit segment size and application of macros # include Calculation of the "C-language" bit segment size and the application of macros

As mentioned in the previous notes, the parent process can get to its terminating state either through the wait function or the WAITPID function, regardless of whether the child process terminates normally or terminates abnormally. However, the information obtained by the normal termination and the abnormal termination of the parent process is different, and the parent process receives the parameter of exit in the child process at normal termination, and the parent process receives the signal nu

follows:myprintf (TEMPLT);be converted to:fprintf (STDERR,TEMPLT);This will not generate a compilation error if the TEMPLT is valid.Incorrect nesting-misnestingThe definition of a macro does not necessarily have to have a complete, paired parenthesis, but it is best to avoid such use in order to avoid errors and improve readability.Problems caused by operator precedence-operator precedence problemSince macros are simply replacements, if the parameter

You cannot use SQL expressions in the Criteria column of a macro. Typically, the direct execution of a macro is just a test. You can either attach a macro to a form, report, or control to respond to an event, or create a custom menu command that executes a macro, after you make sure that the macro is designed correctly. If you want Microsoft Access to temporarily ignore an action, enter False as a condition. Temporarily ignoring the action helps you find the problem in the macro. If you want

Va_list is a group of macros that solve the argument problem in the C language he has so many members:1) va_list type variable:#ifdef _m_alphatypedef struct{char* A0; /*pointertofirsthomedintegerargument*/int offset; /*byteoffsetofnextparameter*/}va_list;#elsetypedef char* Va_list; #endif2) _intsizeof macro, gets the space length occupied by the type, the minimum occupancy length is an integer multiple of int: #define _INTSIZEOF (N) (sizeof (n) +sizeo

Debug macros for Linux C programmingIn the process of completing the project, it is unavoidable to debug, here I give you a I am using a debug macro. Nonsense not much to say, directly on the code.Implementation code/*************************************************************************> File name:debug.c> Author:answer> Mail: [email protected]> Created time:2015 July 23 Thursday 18:19 48 seconds ****************************************************

16.4.2 me the basic idea of this set of macros The main idea of this set of macros is: Use Word "endnote + cross-reference" to create an automated numbering system. In order to reduce duplication of work, written "macro", and made "button", so that "n-step operation, 1-click to solve." 16.4.3 inserts 1 new document numbers (cursor moved to "after text to insert document Number": Suggest you move to the 5