A problem with overloading << (compiler = djgpp)

[Tatu Portin]

1: #include <iostream>
2:
3: typedef struct {
4: double r;
5: double i;
6: } complex;
..
..
..
24: ostream & operator<< (ostream &str, const complex &a)
25: {
26: s << "(" << a.r << " + i" << a.i ")";
27: return s;
28: }

when compiled with gcc:

gcc complex.cc

complex.cc:24: syntax error before `&' token

I think this error has something to do with that 'ostream'. I have #included
<iostream>, so that should not cause this?

[John Harrison]

"Tatu Portin" <ax****@mbnet.f i> wrote in message
news:3y******** *****@read3.ine t.fi...

1: #include <iostream>
2:
3: typedef struct {
4: double r;
5: double i;
6: } complex;
That is C style code, its not wrong but in C++ we prefer

struct complex {
double r;
double i;
};
.
.
.
24: ostream & operator<< (ostream &str, const complex &a)
25: {
26: s << "(" << a.r << " + i" << a.i ")";
27: return s;
28: }

when compiled with gcc:

gcc complex.cc

complex.cc:24: syntax error before `&' token

I think this error has something to do with that 'ostream'. I have
#included <iostream>, so that should not cause this?

You are forgetting that ostream is in the std namespace.

std::ostream & operator<< (std::ostream &str, const complex &a)

Also look at

using std::ostream;

or

using namespace std;

John

[Tatu Portin]

Did help! Thank you, John!