Python regex contents in curly braces
When I want to extract contents between curly braces using python+regex.
The content is following.
void on_sent(
boost::shared_ptr<boost::asio::ip::udp::endpoint> ep_from, // ep to response
boost::shared_ptr<std::vector<uint8_t>> buffer,
boost::system::error_code const& ec,
std::size_t const& bytes_tranferred)
{
if (ec)
{
std::cerr<<__func__<<"() error code : "<<ec.message()<<std::endl;
return ;
}
std::cout<<__func__<<"() sent "<<bytes_tranferred<<" bytes"<<std::endl;
}
When I extract content between if (ec) { ... } I should use following code.
>>> import re
>>> contents = """void on_sent(
... boost::shared_ptr<boost::asio::ip::udp::endpoint> ep_from, // ep to response
... boost::shared_ptr<std::vector<uint8_t>> buffer,
... boost::system::error_code const& ec,
... std::size_t const& bytes_tranferred)
... {
... if (ec)
... {
... std::cerr<<__func__<<"() error code : "<<ec.message()<<std::endl;
... return ;
... }
...
... std::cout<<__func__<<"() sent "<<bytes_tranferred<<" bytes"<<std::endl;
... }"""
>>> re.findall(r"if.*?\{(.*?)\}", contents, re.MULTILINE | re.DOTALL)
['\n std::cerr<<__func__<<"() error code : "<<ec.message()<<std::endl;\n return ;\n ']
Note. I don’t know this is right answer. (maybe not :P ) but, anyway It works.
How about whole function?
>>> re.findall(r"on_sent.*?\{(.*?)\}", a, re.MULTILINE | re.DOTALL)
['\n if (ec)\n {\n std::cerr<<__func__<<"() error code : "<<ec.message()<<std::endl;\n return ;\n ']
This is not what I want. So sad. :(
How can I fix? Before fix code, I should understand what the regex meaning is.
ref : greedy-vs-non-greedy
.*: greedy search (return maxmium statisfied length string).*?: non-greedy search (return minimum satistfied length string)
Oh, Then the problem could resolve easily.
>>> re.findall(r"on_sent.*?\{(.*)\}", a, re.MULTILINE | re.DOTALL)
['\n if (ec)\n {\n std::cerr<<__func__<<"() error code : "<<ec.message()<<std::endl;\n return ;\n }\n\n std::cout<<__func__<<"() sent "<<bytes_tranferred<<" bytes"<<std::endl;\n']
What an easy!