vector of fstream

[Marc Schellens]

I have (or better had) a class wich contains
a fstream (as a private member).
I made a vector of this class.
When I resize() the vector I got several error messages,
about some stuff being private int that context.
Is this gcc (3.2) specific or is there a 'official' reason for this?
thanks,
marc

[Jim Fischer]

Re: vector of fstream

Marc Schellens wrote:[color=blue]
> I have (or better had) a class wich contains
> a fstream (as a private member).
> I made a vector of this class.
> When I resize() the vector I got several error messages,
> about some stuff being private int that context.
> Is this gcc (3.2) specific or is there a 'official' reason for this?[/color]

The C++ iostreams classes are neither CopyConstructab le nor Assignable.
So iostream objects cannot reside in objects / containers that require
these properties (e.g., STL containers). For example:

struct X { std::ofstream out; }

X x1, x2;

// Invoke 'X::X(const X&)' (i.e., class X's copy constructor)
X x3(x2); // ERROR -- member 'out' is not copyable

// Invoke 'X::operator=(c onst X&)'
x1 = x2; // ERROR -- member 'out' is not assignable

--
Jim

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[John Harrison]

Re: vector of fstream


"Jim Fischer" <jfischer_link5 809@now.here.co m> wrote in message
news:_63Ra.2220 $C71.1413@fe01. atl2.webusenet. com...[color=blue]
> Marc Schellens wrote:[color=green]
> > I have (or better had) a class wich contains
> > a fstream (as a private member).
> > I made a vector of this class.
> > When I resize() the vector I got several error messages,
> > about some stuff being private int that context.
> > Is this gcc (3.2) specific or is there a 'official' reason for this?[/color]
>
> The C++ iostreams classes are neither CopyConstructab le nor Assignable.
> So iostream objects cannot reside in objects / containers that require
> these properties (e.g., STL containers). For example:
>
> struct X { std::ofstream out; }
>
> X x1, x2;
>
> // Invoke 'X::X(const X&)' (i.e., class X's copy constructor)
> X x3(x2); // ERROR -- member 'out' is not copyable
>
> // Invoke 'X::operator=(c onst X&)'
> x1 = x2; // ERROR -- member 'out' is not assignable
>
> --
> Jim[/color]

All that is true, but the OP has an fstream in a class, and the class was
put in a vector. So the OP can get around this problem if he can define a
copy constructor and assignment operator for his class. Admittedly this
might be difficult.

john