I wrote two class header files. Before the two headers were included, the project was built successfully. But after they were included in the main.cpp , as shown in the image attached, it was complained while building that
12:54:13: Starting: "/usr/bin/make"
g++ -c -pipe -g -std=c++0x -Wall -W -fPIE -DQT_QML_DEBUG -DQT_DECLARATIVE_DEBUG -I/usr/share/qt5/mkspecs/linux-g++ -I../CPP_Primer_ch2 -I. -o main.o ../CPP_Primer_ch2/main.cpp
In file included from ../CPP_Primer_ch2/wy_StrBlob.h:19:0,
from ../CPP_Primer_ch2/main.cpp:9:
../CPP_Primer_ch2/wy_StrBlobPtr.h:30:30: error: expected ')' before '&' token
make: *** [main.o] Error 1
12:54:15: The process "/usr/bin/make" exited with code 2.
Error while building/deploying project CPP_Primer_ch2 (kit: Desktop)
When executing step 'Make'
Below is the code of wy_StrBlobPtr.h to which error: expected ')' before '&' token
was refering.
#ifndef WY_STRBLOBPTR_H
#define WY_STRBLOBPTR_H
#include <string>
#include <vector>
#include <memory>
#include <wy_StrBlob.h>
#include <stdexcept>
class wy_StrBlobPtr
{
public:
typedef std::vector<std::string> tp;
wy_StrBlobPtr() : curr(0) {}
wy_StrBlobPtr(wy_StrBlob &sb, std::size_t sz = 0) : wp(sb.data), curr(sz) {}
//^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
private:
std::weak_ptr<tp> wp;
std::size_t curr;
};
#endif // WY_STRBLOBPTR_H
What's the problem here?How to fix it?
Update:codes of wy_StrBlob.h. Definitions for the members are omitted for simplicity. Please let me know , if they are needed.
#ifndef WY_STRBLOB_H
#define WY_STRBLOB_H
#include <string>
#include <vector>
#include <memory>
#include <wy_StrBlobPtr.h>
class wy_StrBlobPtr;
class wy_StrBlob
{
friend class wy_StrBlobPtr;
public:
typedef std::vector<std::string>::size_type size_type;
wy_StrBlob() :
data(std::make_shared<std::vector<std::string>>()) {}
wy_StrBlob(std::initializer_list<std::string> il) :
data(std::make_shared<std::vector<std::string>>(il)) {}
size_type size() const { return data->size(); }
bool empty() const { return data->empty(); }
//! add and remove
void push_back(const std::string &s) { data->push_back(s);}
void pop_back();
//! elements access
std::string& front();
const std::string& front() const ;
std::string& back();
const std::string& back() const ;
wy_StrBlobPtr begin(); //return wy_StrBlobPtr to the first element
wy_StrBlobPtr end(); //return one past the last element
private:
std::shared_ptr<std::vector<std::string>> data;
//! throws msg if data[i] isn't valid
void check(size_type i, const std::string &msg) const;
};
#endif // WY_STRBLOB_H
Upadte 2nd:include guards are added.
Remove
#include <wy_StrBlobPtr.h>
from wy_StrBlob.h
class wy_StrBlobPtr
needs the definition of wy_StrBlob
known, however by including the header file, wy_StrBlobPtr
is being defined before wy_StrBlob
symbol is known to the compiler.
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