Although the compiler doesn't have a separate preprocessor, the directives described in this section are processed as if there were one. You use them to help in conditional compilation. Unlike C and C++ directives, you can't use these directives to create macros. A preprocessor directive must ...
The preprocessor directives instruct the compiler how to treat the source code. For example, under certain conditions, you might want the compiler to ignore portions of the code, and under other conditions, you might want that code compiled. The preprocessor directives give you those options and ...
The C preprocessor modifies a source file before handing it over to the compiler, allowing conditional compilation with #ifdef, defining constants with #define, including header files with #include, and using builtin macros such as __FILE__. This page lists the preprocessor directives, or ...
C-preprocessor directives v17 Suggest edits The ECPGPlus C-preprocessor enforces two behaviors that depend on the mode in which you invoke ECPGPlus: PROC mode Non-PROC mode Compiling in PROC mode In PROC mode, ECPGPlus allows you to:...
nothing, in this case the directive has no effect. a line break. Themodule and import directivesare also preprocessing directives. (since C++20) Preprocessing directives must not come from macro expansion. #define EMPTYEMPTY# include <file.h> // not a preprocessing directive ...
which would result in 1 * 5 being evaluated before the addition, not after. Oops! It is also possible to write simply #define [identifier name] which defines [identifier name] without giving it a value. This can be useful in conjunction with another set of directives that allow conditional...
Version or any later version published by the Free Software Foundation. A copy of the license is included in the section entitled “GNU Free Documentation License”. This manual contains no Invariant Sections. The Front-Cover Texts are (a) (see below), and the Back-Cover Texts are (b) (...
可以使用 #warning 指令生成编译器警告,同样可以使用 #error 指令生成错误。 #if SOME_SYMBOL #error This is a compiler Error. #elif SOME_OTHER_SYMBOL #warning This is a compiler Warning. #endif使用条件属性 禁用和恢复编译器警告 Copyright © 2018. All right reserved tastones.com 备案号:鲁IC...
Although the compiler doesn't have a separate preprocessor, the directives described in this section are processed as if there were one. You use them to help in conditional compilation. Unlike C and C++ directives, you can't use these directives to create macros. A preprocessor directive must ...
Although the compiler doesn't have a separate preprocessor, the directives described in this section are processed as if there were one. You use them to help in conditional compilation. Unlike C and C++ directives, you can't use these directives to create macros. A preprocessor directive must ...