No Match for Call

[Atomic_Sheep]

Hi, I've got the following code:

file1.h


#include "file2.h"
#include <QString>

struct ChartProperties
{
QString yvar;
};

file1.cpp


ChartProperties chart1;
if(VariablePresent(chart1.yvar) //etc

file 2.h


#include "file1.h"
#include <QFile>

bool VariablesPresent(QString userVariable);

file2.cpp


bool VariablesPresent(QString userVariable)
{
QFile cVariableEquivalents(//actual system path);
if(!cVariableEquivalents().exists())
//etc
}

I may have missed one or two includes here or there... I've got them in my program, so the problem isn't with the includes I don't think.

The error that I get at compile is:


no match for call to '(QFile) ()'

Any ideas on what I'm doing wrong?

[stampede]

Can you show unmodified part of code that gives you this compilation error ?

[norobro]

no match for call to '(QFile) ()'
The problem is in file2.cpp line #4: cVariableEquivalents()

[ChrisW67]

Line 3 of file2.cpp is in error. You have commented out the closing bracket so that once the pre-processor is finished with it the code reads:


bool VariablesPresent(QString userVariable)
{
QFile cVariableEquivalents(
if(!cVariableEquivalents().exists())

}

which clearly makes no sense. The brackets in that line are unnecessary anyway.

Also, the function is called VariablesPresent() but you try to call VariablePresent(), which will not compile either.

[Atomic_Sheep]

Ok, here's the unmodified version well excerpts at least:

comparison.h


#include <QMainWindow>
#include <QFile>
#include <QDir>
#include <QString>
#include <QTextStream>
#include <QMessageBox>
#include "ui_comparison.h"
#include "filemanager.h"

public:
struct ChartProperties
{
QString yAxisVariable;
QString xAxisVariable;
};


comparison.cpp


#include "comparison.h"

if(VariablesPresent(sChart1.yAxisVariable) && VariablesPresent(sChart1.xAxisVariable))

P.S. the && part wasn't included when I tried to compile it, I've added it later on top of the error and currently am just waiting to get this error fixed to see if this && part is going to cause problems later on in the code.

filemanager.h


#include <QFile>
#include <QDir>
#include <QString>
#include <comparison.h>
#include <QTextStream>

bool VariablesPresent(QString userVariable);

filemanager.cpp


#include "filemanager.h"

bool VariablesPresent(QString userVariable)
{
QFile cVariableEquivalents("/*directory*/");
if(!cVariableEquivalents().exists())

etc...

P.P.S. I'm not sure if bool is what I need but I'm using it for now, might change the function later on.

[ChrisW67]

The problem is still, as norobro pointed out earlier, with line 6 of filemanager.cpp (formerly file2.cpp line 4). You are trying to call QFile::operator() and it doesn't exist, which is precisely what the compiler is telling you. The line should read:


...
if(!cVariableEquivalents.exists())
...

but it will only do something sensible if line 5 actually contains something likely to be a file name.

[Atomic_Sheep]

OOOOOH, thanks, simple fix... I just had to remove the () brackets from all subsequent uses and now it's all good, thanks.