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Why won't this list remove_if code compile

Hi

I have a class CRequest with a function:
bool IsFinished() const;

I have a list of these CRequests - list<CRequestmy list.

I create a function object to find if a CRequest is finished:
class is_finished : public std::unary_func tion<CRequest, bool>
{
public:
bool operator() (CRequest req) { return req.IsFinished( ); }
};

And I use remove_if like this:
m_RequestList.r emove_if(is_fin ished());

But I get a compile error:
error C2664: 'remove_if' : cannot convert parameter 1 from 'class
is_finished' to 'class std::binder2nd< struct std::not_equal_ to<class
CRequest'
No constructor could take the source type, or constructor overload
resolution was ambiguous

How can I fix this?
Jun 27 '08 #1
3 2590
On 2008-05-24 11:05:20 -0400, "Angus" <no****@gmail.c omsaid:
>
I have a class CRequest with a function:
bool IsFinished() const;

I have a list of these CRequests - list<CRequestmy list.

I create a function object to find if a CRequest is finished:
class is_finished : public std::unary_func tion<CRequest, bool>
{
public:
bool operator() (CRequest req) { return req.IsFinished( ); }
};

And I use remove_if like this:
m_RequestList.r emove_if(is_fin ished());

But I get a compile error:
error C2664: 'remove_if' : cannot convert parameter 1 from 'class
is_finished' to 'class std::binder2nd< struct std::not_equal_ to<class
CRequest'
No constructor could take the source type, or constructor overload
resolution was ambiguous

How can I fix this?
Get a newer compiler.

--
Pete
Roundhouse Consulting, Ltd. (www.versatilecoding.com) Author of "The
Standard C++ Library Extensions: a Tutorial and Reference
(www.petebecker.com/tr1book)

Jun 27 '08 #2
Hi!

Angus schrieb:
public:
bool operator() (CRequest req) { return req.IsFinished( ); }
I guess the operator should be a const function.

Frank
Jun 27 '08 #3
"Angus" <no****@gmail.c omwrote:
I have a class CRequest with a function:
bool IsFinished() const;

I have a list of these CRequests - list<CRequestmy list.

I create a function object to find if a CRequest is finished:
class is_finished : public std::unary_func tion<CRequest, bool>
{
public:
bool operator() (CRequest req) { return req.IsFinished( ); }
};

And I use remove_if like this:
m_RequestList.r emove_if(is_fin ished());

But I get a compile error:
error C2664: 'remove_if' : cannot convert parameter 1 from 'class
is_finished' to 'class std::binder2nd< struct std::not_equal_ to<class
CRequest'
No constructor could take the source type, or constructor overload
resolution was ambiguous

How can I fix this?
Try this:

class CRequest
{
public:
bool isFinished() const;
};

void fn( list<CRequestls t )
{
lst.remove_if( mem_fun_ref( &CRequest::isFi nished ) );
}
Jun 27 '08 #4

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