Why Doesn't C++ Accept This OFSTREAM VECTOR?

[Marina]

I get an "access violation" when I use someting like this:

@@@@@@@@@@@@@@
string tempo;
const char *output;
vector <ofstream> outs(3);
....
....
open_output=(const char *)tempo.c_str();
ofstream out0(open_output, ios:ut | ios:ut);
outs[0]=out0;

@@@@@@@@@@@@@@
This access violation comes only when
the line

outs[0]=out0;

is included.
Please help. I do need a vector ot "ofstream" type.

Thank you!

Marina

 

[Victor Bazarov]

I get an "access violation" when I use someting like this:

@@@@@@@@@@@@@@
string tempo;
const char *output;
vector <ofstream> outs(3);

This shouldn't compile. 'ofstream' doesn't satisfy the requirement for
elements of 'vector': it is not "copy-constructible".

...
...
open_output=(const char *)tempo.c_str();

There is no need to cast it. 'c_str()' already returns const char*.

ofstream out0(open_output, ios:ut | ios:ut); ^^^^^^^^^^^^^^^^^^^^^^ Huh?
outs[0]=out0;

There is no copy semantics for ofstream. This simply shouldn't compile.

Why can't you simply say

outs[0].open(open_output);

@@@@@@@@@@@@@@
This access violation comes only when
the line

outs[0]=out0;

is included.
Please help. I do need a vector ot "ofstream" type.

You can't have it. Create a vector of pointers to ofstream.

V

 

[Marina]

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From: Victor Bazarov <[email protected]>
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Subject: Re: Why Doesn't C++ Accept This OFSTREAM VECTOR?
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I get an "access violation" when I use someting like this:

@@@@@@@@@@@@@@
string tempo;
const char *output;
vector <ofstream> outs(3);

This shouldn't compile. 'ofstream' doesn't satisfy the requirement for
elements of 'vector': it is not "copy-constructible".

...
...
open_output=(const char *)tempo.c_str();

There is no need to cast it. 'c_str()' already returns const char*.

ofstream out0(open_output, ios:ut | ios:ut); ^^^^^^^^^^^^^^^^^^^^^^ Huh?
outs[0]=out0;

There is no copy semantics for ofstream. This simply shouldn't compile.

Why can't you simply say

outs[0].open(open_output);

@@@@@@@@@@@@@@
This access violation comes only when
the line

outs[0]=out0;

is included.
Please help. I do need a vector ot "ofstream" type.

You can't have it. Create a vector of pointers to ofstream.

Thank you, Bazarov!
It worked fine.

Later...

Marina