operator= ?

[JustSomeGuy]

I want to have a method in my class that will set its value from a
right hand side thats a std::string

ie..

myClass c;
std::string x("Hello");
c = x;

what method must I implement in myclass to do this?

[Cat]

AFAIK,

void myClass::operator=(std::string& str);

[Cat]

Whoops.. that should probably be:

myClass& myClass::operator=(std::string& str)

[ferdinand.stefanus]

Cat wrote:

Whoops.. that should probably be:

myClass& myClass::operator=(std::string& str)

Or better yet,

myClass& myClass::operator=(const std::string& str);

As I assume the OP does not need to modify str.

[Ian Collins]

JustSomeGuy wrote:

I want to have a method in my class that will set its value from a
right hand side thats a std::string

ie..

myClass c;
std::string x("Hello");
c = x;

what method must I implement in myclass to do this?

myClass& operator=(const std::string);

--
Ian Collins.

[Daniel T.]

In article <11**********************@z34g2000cwc.googlegroups .com>,
fe****************@gmail.com wrote:

Cat wrote:

Whoops.. that should probably be:

myClass& myClass::operator=(std::string& str)

Or better yet,

myClass& myClass::operator=(const std::string& str);

As I assume the OP does not need to modify str.

In that vain. Is there a table somewhere on the net that shows the
standard operator signatures?
--
Magic depends on tradition and belief. It does not welcome observation,
nor does it profit by experiment. On the other hand, science is based
on experience; it is open to correction by observation and experiment.

[John Carson]

"Daniel T." <po********@earthlink.net> wrote in message
news:po******************************@news.east.ea rthlink.net

In article <11**********************@z34g2000cwc.googlegroups .com>,
fe****************@gmail.com wrote:

Cat wrote:

Whoops.. that should probably be:

myClass& myClass::operator=(std::string& str)

Or better yet,

myClass& myClass::operator=(const std::string& str);

As I assume the OP does not need to modify str.

In that vain. Is there a table somewhere on the net that shows the
standard operator signatures?
--
Magic depends on tradition and belief. It does not welcome
observation, nor does it profit by experiment. On the other hand,
science is based on experience; it is open to correction by
observation and experiment.

I don't know what you mean by "standard operator signatures", but Vol I of
Bruce Eckel's Thinking in C++ has a chapter showing how to define every
user-definable operator. It is Chapter 12.

http://mindview.net/Books/TICPP/ThinkingInCPP2e.html
--
John Carson

[Richard Herring]

In message <11***************@drone2-svc-skyt.qsi.net.nz>, Ian Collins
<ia******@hotmail.com> writes

JustSomeGuy wrote:

I want to have a method in my class that will set its value from a
right hand side thats a std::string
ie..
myClass c;
std::string x("Hello");
c = x;
what method must I implement in myclass to do this?

myClass& operator=(const std::string);

What's the "const" for?

--
Richard Herring

[Ben Pope]

Richard Herring wrote:

In message <11***************@drone2-svc-skyt.qsi.net.nz>, Ian Collins
<ia******@hotmail.com> writes

JustSomeGuy wrote:

I want to have a method in my class that will set its value from a
right hand side thats a std::string
ie..
myClass c;
std::string x("Hello");
c = x;
what method must I implement in myclass to do this?

myClass& operator=(const std::string);

What's the "const" for?

He probably meant:

myClass& operator=(const std::string&)

Ben Pope
--
I'm not just a number. To many, I'm known as a string...

[Ian Collins]

Ben Pope wrote:

Richard Herring wrote:

In message <11***************@drone2-svc-skyt.qsi.net.nz>, Ian Collins
<ia******@hotmail.com> writes

JustSomeGuy wrote:

I want to have a method in my class that will set its value from a
right hand side thats a std::string
ie..
myClass c;
std::string x("Hello");
c = x;
what method must I implement in myclass to do this?

myClass& operator=(const std::string);

What's the "const" for?

He probably meant:

myClass& operator=(const std::string&)

In this case, no. At least with the STL I use it's more efficient to
pass strings by value....

To the OP - it's const because it's value isn't changed in the function.

--
Ian Collins.

[Richard Herring]

In message <11***************@drone2-svc-skyt.qsi.net.nz>, Ian Collins
<ia******@hotmail.com> writes

Ben Pope wrote:

Richard Herring wrote:

In message <11***************@drone2-svc-skyt.qsi.net.nz>, Ian Collins
<ia******@hotmail.com> writes

JustSomeGuy wrote:

> I want to have a method in my class that will set its value from a
> right hand side thats a std::string
> ie..
> myClass c;
> std::string x("Hello");
> c = x;
> what method must I implement in myclass to do this?
>
myClass& operator=(const std::string);

What's the "const" for?

He probably meant:

myClass& operator=(const std::string&)

In this case, no. At least with the STL I use it's more efficient to
pass strings by value....

Measurably?
To the OP - it's const because it's value isn't changed in the function.

(a) How do you know? It's his function, not yours ;-)

(b) It's implementation detail which has no place in a function
declaration, since it doesn't affect the function's signature.

--
Richard Herring