Hi All,
Not sure if this is a c++ issue or a compiler issue.
I have the following in a class:
template<class T>
bool Utility::getInput(T& i, T low, T up){
bool result = false;
if(cin >i){
if((i >= low)&&(i <= up)){
result = true;
}
} else {
cin.clear();
cin.ignore(1000, '\n');
}
return result;
}
in another file and class I have :
Utility utility;
utility.getInput(sal, 0.0, 999999.99);
utility.getInput(sid, 0, 999999);
Now, if I put all this in one file it compiles no worries. But, if I compile
it as is i get an error from the linker:
[linker error] Undefined reference to 'bool
Utility::getInput<double>(double&, double, double)'
Why if the linker can't find the reference to 'bool
Utility::getInput<double>(double&, double, double)' does it not complain
about the (int&, int, int) reference that comes before it in the code? How
can I resolve the error? The only linker errors I've had before have been
related to not including files in the compile command, but this is something
else....
Thanks for your help.
Regards
Michael 3 2094
On Mar 28, 12:51 pm, "michael" <s...@begone.netwrote:
Hi All,
Not sure if this is a c++ issue or a compiler issue.
I have the following in a class:
template<class T>
bool Utility::getInput(T& i, T low, T up){
bool result = false;
if(cin >i){
if((i >= low)&&(i <= up)){
result = true;
}
} else {
cin.clear();
cin.ignore(1000, '\n');
}
return result;
}
in another file and class I have :
Utility utility;
utility.getInput(sal, 0.0, 999999.99);
utility.getInput(sid, 0, 999999);
Now, if I put all this in one file it compiles no worries. But, if I compile
it as is i get an error from the linker:
[linker error] Undefined reference to 'bool
Utility::getInput<double>(double&, double, double)'
Why if the linker can't find the reference to 'bool
Utility::getInput<double>(double&, double, double)' does it not complain
about the (int&, int, int) reference that comes before it in the code? How
can I resolve the error? The only linker errors I've had before have been
related to not including files in the compile command, but this is something
else....
Thanks for your help.
Regards
Michael
can you post a minimal testcase that compiles but does not link to
demonstrate your problem?
m.
michael schrieb:
Hi All,
Not sure if this is a c++ issue or a compiler issue.
I have the following in a class:
template<class T>
bool Utility::getInput(T& i, T low, T up){
bool result = false;
if(cin >i){
if((i >= low)&&(i <= up)){
result = true;
}
} else {
cin.clear();
cin.ignore(1000, '\n');
}
return result;
}
in another file and class I have :
Utility utility;
utility.getInput(sal, 0.0, 999999.99);
utility.getInput(sid, 0, 999999);
Now, if I put all this in one file it compiles no worries. But, if I compile
it as is i get an error from the linker:
[linker error] Undefined reference to 'bool
Utility::getInput<double>(double&, double, double)'
Why if the linker can't find the reference to 'bool
Utility::getInput<double>(double&, double, double)' does it not complain
about the (int&, int, int) reference that comes before it in the code? How
can I resolve the error? The only linker errors I've had before have been
related to not including files in the compile command, but this is something
else....
Thanks for your help.
Regards
Michael
Is the definition and implementation of this function inside the same
header? You have to put the definition into the same header or into
one that is included by this header.
On Mar 28, 2:51 pm, "michael" <s...@begone.netwrote:
Hi All,
Not sure if this is a c++ issue or a compiler issue.
I have the following in a class:
template<class T>
bool Utility::getInput(T& i, T low, T up){
bool result = false;
if(cin >i){
if((i >= low)&&(i <= up)){
result = true;
}
} else {
cin.clear();
cin.ignore(1000, '\n');
}
return result;
}
in another file and class I have :
Utility utility;
utility.getInput(sal, 0.0, 999999.99);
utility.getInput(sid, 0, 999999);
Now, if I put all this in one file it compiles no worries. But, if I compile
it as is i get an error from the linker:
[linker error] Undefined reference to 'bool
Utility::getInput<double>(double&, double, double)'
Why if the linker can't find the reference to 'bool
Utility::getInput<double>(double&, double, double)' does it not complain
about the (int&, int, int) reference that comes before it in the code? How
can I resolve the error? The only linker errors I've had before have been
related to not including files in the compile command, but this is something
else....
Thanks for your help.
Regards
Michael
The problem is not in the code.You seem to not know how to device
modular (multi-file projects) programming with C++ .Read the
documentation for your compiler.
[linker error] Undefined reference to 'bool
Utility::getInput<double>(double&, double, double)'
this means that you have refered to(called/used) an
identifier(function in this context) that the linker can not find in
any file. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics
by: Patrick Kowalzick |
last post by:
Dear all,
I have a question about default template parameters.
I want to have a second template parameter which as a default parameter,
but depends on the first one (see below). Is something...
|
by: Sebastian Faust |
last post by:
Hi,
I have 4 questions related to templates.
I wanna do something like the following:
template<typename T>
class Template
{
public:
Template_Test<T>()
|
by: Adam Parkin |
last post by:
Hello, all I'm having a problem with friend functions in a templatized Queue
class I'm writing using linked lists. The problem is that I can't get the
friend function to be able to access private...
|
by: Drew McCormack |
last post by:
I have a C++ template class which contains a static variable whose
construction registers the class with a map. Something like this:
template <typename T>
class M {
static Registrar<M>...
|
by: Leslaw Bieniasz |
last post by:
Cracow, 16.09.2004
Hi,
I have a problem with compiling the following construction involving
cross-calls of class template methods, with additional inheritance.
I want to have three class...
|
by: Siegfried Weiss |
last post by:
Hi guys,
i give up finding a solution by reading or by trial & error. Hope, YOU
can help me! (Sorry for my rather long posting.)
Stroustrup says, that templates could be declared with
- type...
|
by: Chris |
last post by:
I am having a very strange problem involving virtual
functions in template classes. First of all, here is an
extremely simplified structure of the two classes I am
having problems with.
...
|
by: aaragon |
last post by:
Hi everyone. A very simple question. I would like to know what is
better in terms of performance. I want to use a simple function to
obtain the minimum of two values. One way could be using a...
|
by: Hamilton Woods |
last post by:
Diehards,
I developed a template matrix class back around 1992 using Borland C++ 4.5
(ancestor of C++ Builder) and haven't touched it until a few days ago. I
pulled it from the freezer and...
|
by: danilo.turina |
last post by:
Hi all,
today I encountered a problem that I'm only able to solve by using
reinterpret_cast (and I'd like to avoid it).
This was my code until yesterday (omitting includes, "using namespace"...
|
by: DolphinDB |
last post by:
Tired of spending countless mintues downsampling your data? Look no further!
In this article, you’ll learn how to efficiently downsample 6.48 billion high-frequency records to 61 million...
|
by: isladogs |
last post by:
The next Access Europe meeting will be on Wednesday 6 Mar 2024 starting at 18:00 UK time (6PM UTC) and finishing at about 19:15 (7.15PM).
In this month's session, we are pleased to welcome back...
|
by: Vimpel783 |
last post by:
Hello!
Guys, I found this code on the Internet, but I need to modify it a little. It works well, the problem is this: Data is sent from only one cell, in this case B5, but it is necessary that data...
|
by: jfyes |
last post by:
As a hardware engineer, after seeing that CEIWEI recently released a new tool for Modbus RTU Over TCP/UDP filtering and monitoring, I actively went to its official website to take a look. It turned...
|
by: CloudSolutions |
last post by:
Introduction:
For many beginners and individual users, requiring a credit card and email registration may pose a barrier when starting to use cloud servers. However, some cloud server providers now...
|
by: Defcon1945 |
last post by:
I'm trying to learn Python using Pycharm but import shutil doesn't work
|
by: Shællîpôpï 09 |
last post by:
If u are using a keypad phone, how do u turn on JavaScript, to access features like WhatsApp, Facebook, Instagram....
|
by: af34tf |
last post by:
Hi Guys, I have a domain whose name is BytesLimited.com, and I want to sell it. Does anyone know about platforms that allow me to list my domain in auction for free. Thank you
|
by: isladogs |
last post by:
The next Access Europe User Group meeting will be on Wednesday 3 Apr 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM).
In this session, we are pleased to welcome former...
| |