C++-overview4

对C++语言的浏览,供对C++语言有兴趣的读者作为参考

An Overview of C++

Douglas C. Schmidt

C++ Overview

An Overview of C++ Douglas C. Schmidt Professor d.schmidt@vanderbilt.edu doc.xuehai.net～schmidt/ Department of EECS Vanderbilt University (615) 343-8197

C++ was designed at AT&T Bell Labs by Bjarne Stroustrup in the early 80’s– The original cfront translated C++ into C for portability However, this was di cult to debug and potentially ine cient– Many native host machine compilers now exist e.g., Borland, DEC, GNU, HP, IBM, Microsoft, Sun, Symantec, etc. C++ is a mostly upwardly compatible extension of C that provides: 1. 2. 3. 4. Stronger typechecking Support for data abstraction Support for object-oriented programming Support for generic programming

doc.xuehai.net～schmidt/PDF/C++-overview.pdf June 20, 2010

Vanderbilt University

1

An Overview of C++

Douglas C. Schmidt

An Overview of C++

Douglas C. Schmidt

C++ Design Goals As with C, run-time e ciency is important– Unlike other languages (e.g., Ada) complicated run-time libraries have not traditionally been required for C++ Note, that there is no language-speci c support for concurrency, persistence, or distribution in C++ Compatibility with C libraries& traditional development tools is emphasized, e.g.,– Object code reuse The storage layout of structures is compatible with C e.g., support for X-windows, standard ANSI C library,& UNIX/WIN32 system calls via extern block– C++ works with the make recompilation utility Vanderbilt University 2

C++ Design Goals (cont’d) “As close to C as possible, but no closer”– i.e., C++ is not a proper superset of C→ backwards compatibility is not entirely maintained Typically not a problem in practice... Note, certain C++ design goals con ict with modern techniques for: 1. Compiler optimization– e.g., pointers to arbitrary memory locations complicate register allocation& garbage collection 2. Software engineering– e.g., separate compilation complicates inlining due to di culty of interprocedural analysis– Dynamic memory management is error-prone Vanderbilt University 3

第1页下一页