我想用C++ 11的正则表达式来完成一个非常简单的过滤任务,但是我无法让它像我想要的那样工作。于是我开始写一个单独的演示程序。std :: regex与g ++失败?
事情是,最简单的事情失败悲惨。例如:
#include <regex>
#include <string>
#include <iostream>
int main()
{
std::vector<std::string> inputs;
inputs.push_back("1");
inputs.push_back("123");
inputs.push_back("a");
inputs.push_back("apple");
inputs.push_back(":apple3.worm");
std::string pattern("[0-9]");
std::regex r(pattern, std::regex_constants::grep);
for(auto const &s: inputs)
{
bool ok = std::regex_match(s, r);
std::cout << (ok?"POS":"NEG") << ": " << s << std::endl;
}
return 0;
}
编译时没有与g++ -Wextra -pedantic -std=c++11 -O3 rfail.cpp -o rfail
警告。输出:当我[[:digit:]]
取代[0-9]
POS: 1
NEG: 123
POS: a
NEG: apple
NEG: :apple3.worm
同样happend。发生什么事?我做错了什么?
更新:
$ g++ -v
Using built-in specs.
COLLECT_GCC=g++
COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-linux-gnu/4.8/lto-wrapper
Target: x86_64-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu 4.8.4-2ubuntu1~14.04.3' --with-bugurl=file:///usr/share/doc/gcc-4.8/README.Bugs --enable-languages=c,c++,java,go,d,fortran,objc,obj-c++ --prefix=/usr --program-suffix=-4.8 --enable-shared --enable-linker-build-id --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.8 --libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu --enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-gnu-unique-object --disable-libmudflap --enable-plugin --with-system-zlib --disable-browser-plugin --enable-java-awt=gtk --enable-gtk-cairo --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-4.8-amd64/jre --enable-java-home --with-jvm-root-dir=/usr/lib/jvm/java-1.5.0-gcj-4.8-amd64 --with-jvm-jar-dir=/usr/lib/jvm-exports/java-1.5.0-gcj-4.8-amd64 --with-arch-directory=amd64 --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --enable-objc-gc --enable-multiarch --disable-werror --with-arch-32=i686 --with-abi=m64 --with-multilib-list=m32,m64,mx32 --with-tune=generic --enable-checking=release --build=x86_64-linux-gnu --host=x86_64-linux-gnu --target=x86_64-linux-gnu
Thread model: posix
gcc version 4.8.4 (Ubuntu 4.8.4-2ubuntu1~14.04.3)
你应该给我们更多关于你的'g ++'的信息 –