I picked (ie copy-pasted) the following example from Boost documentation (http://www.boost.org/doc/libs/1_55_0b1/libs/assign/doc/index.html#operator+=):
#include <boost/assign/std/vector.hpp> // for 'operator+=()'
#include <boost/assert.hpp>
using namespace std;
using namespace boost::assign; // bring 'operator+=()' into scope
{
vector<int> values;
values += 1,2,3,4,5,6,7,8,9; // insert values at the end of the container
BOOST_ASSERT( values.size() == 9 );
BOOST_ASSERT( values[0] == 1 );
BOOST_ASSERT( values[8] == 9 );
}
Which throws the following error:
$ g++ boost_assign.cpp
boost_assign.cpp:6:1: error: expected unqualified-id before ‘{’ token
{
^
What's wrong ? Are the boost examples not directly copy-paste-run-able ?
Those examples are not copy-paste-run-able. Code enclosed in braces needs to be pasted somewhere in a function.
Related
I'm using react-native-pusher-push-notifications to get notifications in my app when trying to compile my app ,I got this error:
Unknown type name 'namespace'
namespace std{ //Expected ';' after top level declarator
using :: va_list;
}
I tried to fix my code in this way but got the same error :
#ifndef __CSTDARG_HEADER #define __CSTDARG_HEADER
#include <stdarg.h>
namespace std{
using :: va_list;
}
#else
typedef struct std std; // Sets up incomplete type for C code
#endif
I have declared a function in the c++ file as stated in the documentation and called it in the .ned file. But it gives the following error.
error:expected constructor, destructor, or type conversion before ‘(’ token Define_Function(dijkstra, 1);
The following is my c++ file.
#include <omnetpp.h>
#include "stdio.h"
#include "Node.h"
#include "cdelaychannel.h"
Define_Function(dijkstra, 1);
double dijkstra(double start = 1){
....
....
}
In my network description file, I've called the function.
package myproject;
#license(LGPL);
dijkstra(1.0);
Why is it giving me the error?
If you want to create a function for using it in NED files, you have to do it as described in OMNeT++ Manual. An example could be the following:
static cNEDValue ned_foo(cComponent *context, cNEDValue argv[], int argc)
int a = (long) argv[0];
int b = (long) argv[1];
return a*b;
}
Define_NED_Function(ned_foo,"int ned_foo(int a, int b)");
I've been working on a C++ project using Boost, and between compiles, I must have upgraded something in boost without meaning to or something, because now Boost dependencies won't compile:
In file included from /usr/include/boost/thread/pthread/mutex.hpp:14:0,
from /usr/include/boost/thread/mutex.hpp:16,
from /usr/include/boost/thread/pthread/thread_data.hpp:12,
from /usr/include/boost/thread/thread.hpp:17,
from /usr/include/boost/thread.hpp:13,
from /blah.h:4,
from bluh.h:3,
from bleh/main.cpp:4:
/usr/include/boost/thread/xtime.hpp:23:5: error: expected identifier before numeric constant
/usr/include/boost/thread/xtime.hpp:23:5: error: expected '}' before numeric constant
/usr/include/boost/thread/xtime.hpp:23:5: error: expected unqualified-id before numeric constant
/usr/include/boost/thread/xtime.hpp:46:14: error: expected type-specifier before 'system_time'
In file included from /usr/include/boost/thread/pthread/mutex.hpp:14:0,
from /usr/include/boost/thread/mutex.hpp:16,
from /usr/include/boost/thread/pthread/thread_data.hpp:12,
from /usr/include/boost/thread/thread.hpp:17,
from /usr/include/boost/thread.hpp:13,
from /blah,
from /bleh,(changed these names, obviously)
from /bluh /main.cpp:4:
/usr/include/boost/thread/xtime.hpp: In function 'int xtime_get(xtime*, int)':
/usr/include/boost/thread/xtime.hpp:73:40: error: 'get_system_time' was not declared in this scope
/usr/include/boost/thread/xtime.hpp:73:40: note: suggested alternative:
/usr/include/boost/thread/thread_time.hpp:19:24: note: 'boost::get_system_time'
/usr/include/boost/thread/xtime.hpp: At global scope:
/usr/include/boost/thread/xtime.hpp:88:1: error: expected declaration before '}' token
make[2]: *** [CMakeFiles/edge_based_tracker.dir/main.o] Error 1
make[1]: *** [CMakeFiles/edge_based_tracker.dir/all] Error 2
make: *** [all] Error 2
Any ideas? I tried changing TIME_UTC to TIME_UTC_ as this was recommended to me on another site, but that didn't seem to help.
EDIT: The Boost Version is Version: 1.48.0.2. I've attached xtime below:
// Copyright (C) 2001-2003
// William E. Kempf
// Copyright (C) 2007-8 Anthony Williams
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
#ifndef BOOST_XTIME_WEK070601_HPP
#define BOOST_XTIME_WEK070601_HPP
#include <boost/thread/detail/config.hpp>
#include <boost/cstdint.hpp>
#include <boost/thread/thread_time.hpp>
#include <boost/date_time/posix_time/conversion.hpp>
#include <boost/config/abi_prefix.hpp>
namespace boost {
enum xtime_clock_types
{
TIME_UTC=1 //LINE 23
// TIME_TAI,
// TIME_MONOTONIC,
// TIME_PROCESS,
// TIME_THREAD,
// TIME_LOCAL,
// TIME_SYNC,
// TIME_RESOLUTION
};
struct xtime
{
#if defined(BOOST_NO_INT64_T)
typedef int_fast32_t xtime_sec_t; //INT_FAST32_MIN <= sec <= INT_FAST32_MAX
#else
typedef int_fast64_t xtime_sec_t; //INT_FAST64_MIN <= sec <= INT_FAST64_MAX
#endif
typedef int_fast32_t xtime_nsec_t; //0 <= xtime.nsec < NANOSECONDS_PER_SECOND
xtime_sec_t sec;
xtime_nsec_t nsec;
operator system_time() const
{
return boost::posix_time::from_time_t(0)+
boost::posix_time::seconds(static_cast<long>(sec))+
#ifdef BOOST_DATE_TIME_HAS_NANOSECONDS
boost::posix_time::nanoseconds(nsec);
#else
boost::posix_time::microseconds((nsec+500)/1000);
#endif
}
};
inline xtime get_xtime(boost::system_time const& abs_time)
{
xtime res;
boost::posix_time::time_duration const time_since_epoch=abs_time-boost::posix_time::from_time_t(0);
res.sec=static_cast<xtime::xtime_sec_t>(time_since_epoch.total_seconds());
res.nsec=static_cast<xtime::xtime_nsec_t>(time_since_epoch.fractional_seconds()*(1000000000/time_since_epoch.ticks_per_second()));
return res;
}
inline int xtime_get(struct xtime* xtp, int clock_type)
{
if (clock_type == TIME_UTC)
{
*xtp=get_xtime(get_system_time());
return clock_type;
}
return 0;
}
inline int xtime_cmp(const xtime& xt1, const xtime& xt2)
{
if (xt1.sec == xt2.sec)
return (int)(xt1.nsec - xt2.nsec);
else
return (xt1.sec > xt2.sec) ? 1 : -1;
}
} // namespace boost
#include <boost/config/abi_suffix.hpp>
#endif //BOOST_XTIME_WEK070601_HPP
EDIT: To make it clear, the code is failing on an import of boost/thread.hpp
For those running into the same issue and struggling to find the solution here.
Derived from noodlebox' link (https://svn.boost.org/trac/boost/ticket/6940):
You can edit /usr/include/boost/thread/xtime.hpp (or whereever your xtime.hpp lies)
and change all occurrences of TIME_UTC to TIME_UTC_ - Probably around lines 23 and 71.
i.e. sed -i 's/TIME_UTC/TIME_UTC_/g' /usr/include/boost/thread/xtime.hpp
If you're getting syntax errors when using Boost, you may need to compile your code with -std=c++11.
The TIME_UTC issue you might have read about is a side effect of using c++11. TIME_UTC is now defined as a macro in c++11, so you will need to either replace all instances of TIME_UTC with TIME_UTC_, or just use a newer (1.50.0+) version of Boost where this has been fixed already.
See: https://svn.boost.org/trac/boost/ticket/6940
Since you do not show your code, we can only guess. My guess is that you define TIME_UTC macro somewhere in your code. This macro messes-up xtime.hpp header.
This compiles fine in MSVC but gcc complains. The code on ideone. I don't understand what is wrong by passing the iterators by reference.
The error
prog.cpp: In function ‘void FindType()’:
prog.cpp:8: error: no matching function for call to ‘FindType(__gnu_cxx::__normal_iterator<Var**, std::vector<Var*, std::allocator<Var*> > >, __gnu_cxx::__normal_iterator<Var**, std::vector<Var*, std::allocator<Var*> > >)’
prog.cpp:4: note: candidates are: void FindType(__gnu_cxx::__normal_iterator<Var**, std::vector<Var*, std::allocator<Var*> > >&, __gnu_cxx::__normal_iterator<Var**, std::vector<Var*, std::allocator<Var*> > >&)
prog.cpp:5: note: void FindType()
prog.cpp:8: error: return-statement with a value, in function returning 'void'
The code
#include <vector>
using namespace std;
class Var {};
void FindType(vector<Var*>::iterator&b, vector<Var*>::iterator&e){}
void FindType()
{
vector<Var*> ls;
return FindType(ls.begin(), ls.end());
}
Pass const references. The .begin() and .end() calls return rvalues.
Revision: However, as you have observed in the comments below, you cannot do ++b if b is a const reference. Your idea below seems best in that case: pass that iterator by value.
I'm trying to use c_escape_ch_p (see here) from boost::spirit to parse an escaped C++ string. But I'm getting a compiler error. Here is my code:
#include <boost/config/warning_disable.hpp>
#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/home/classic/utility/escape_char.hpp>
#include <boost/spirit/home/classic/utility/confix.hpp>
#include <iostream>
#include <string>
namespace client {
namespace qi = boost::spirit::qi;
namespace ascii = boost::spirit::ascii;
template <typename Iterator>
bool parse(Iterator first, Iterator last) {
using qi::char_;
qi::rule< Iterator, std::string(), ascii::space_type > text;
using namespace boost::spirit::classic;
qi::rule<Iterator, std::string()> myword2 =
confix_p('"', *c_escape_ch_p, '"') ; // ERROR!
text = myword2;
bool r = qi::phrase_parse(first, last, text, ascii::space);
if (first != last)
return false;
return r;
}
}
int main () {
std::string s = "\"foo\"";
bool ok = client::parse(s.begin(), s.end());
std::cout << "OK? " << (ok ? "y" : "n") << std::endl;
return 0;
}
The compiler error is a failed static assert instantiated from the line with confix:
// Report invalid expression error as early as possible.
// If you got an error_invalid_expression error message here,
// then the expression (expr) is not a valid spirit qi expression.
BOOST_SPIRIT_ASSERT_MATCH(qi::domain, Expr);
So, it says it's not a valid expression. How is it used correctly?
P.S.: I'm using Boost 1.45.
You are trying to combine classic (old, V1, ...) boost::spirit::classic and (new, V2) boost::spirit::qi.
This is not going to work. The newer stuff is a complete, and incompatible, rewrite. See the 'Porting from Spirit 1.8.x' notes in the documentation.
As for the question on how to parse escaped C/C++ strings using boost::spirit::qi, the following article will be helpful:
Parsing Escaped String Input Using Spirit.Qi