Overview

Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. High Quality Content by WIKIPEDIA articles! In the C and C++ programming languages, #pragma once is a non-standard but widely supported preprocessor directive designed to cause the current source file to be included only once in a single compilation. Thus, #pragma once serves the same purpose as #include guards, but with several advantages, including: less code, avoiding name clashes, and improved compile speed. See the article on #include guards for an example of a situation in which one or the other of these methods must be used. Using #pragma once instead of include guards will typically increase compilation speed since it is a higher-level mechanism; the compiler itself can compare filenames or inodes without having to invoke the C preprocessor to scan the header for #ifndef and #endif. Some compilers such as GCC include special speedup code to recognize and optimize the handling of include guards, and thus little or no speedup benefit is obtained from the use of #pragma once.

Full Product Details

9786132147103

Table of Contents

Reviews

Author Information

Tab Content 6

Customer Reviews

Recent Reviews

Countries Available