473,320 Members | 1,987 Online
Bytes | Software Development & Data Engineering Community
Post Job

Home Posts Topics Members FAQ

Join Bytes to post your question to a community of 473,320 software developers and data experts.

valid C++

gcc 3.4 complains when a
derived class uses an indentifier which is
defined in the base class and the base class
is the template parameter.

eg. something like:

class B
{
protected:
int member;
};

template< class base>
class D: public base
{
public:
void aFun();
};

template< class base>
void D< base>::aFun()
{
member = 1;
}

template class D< B>;

It says then:
member undecalred (first use of this function).
Isn't that valid C++?

thanks,
marc

Jul 22 '05 #1
4 1366

"Marc Schellens" <m_*********@hotmail.com> wrote in message
gcc 3.4 complains when a
derived class uses an indentifier which is
defined in the base class and the base class
is the template parameter.

[snip]
http://www.parashift.com/c++-faq-lit...html#faq-34.17

Sharad
Jul 22 '05 #2
* Marc Schellens:
gcc 3.4 complains when a
derived class uses an indentifier which is
defined in the base class and the base class
is the template parameter.

eg. something like:

class B
{
protected:
int member;
};

template< class base>
class D: public base
{
public:
void aFun();
};

template< class base>
void D< base>::aFun()
{
member = 1;
}

template class D< B>;

It says then:
member undecalred (first use of this function).

Isn't that valid C++?


No, but older compilers may accept it (also, VC 7.1 accepts it).

The problem is that when seeing 'member = 1' for the first time the
compiler doesn't have the slightest cue about where 'member' comes from,
or whether it comes from anywhere.

To give it that clue you can use a 'using' statement in class D,
or you can qualify 'member' in some way, e.g. 'this.member'.

--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?
Jul 22 '05 #3

"Alf P. Steinbach" <al***@start.no> wrote in message
* Marc Schellens:
To give it that clue you can use a 'using' statement in class D,
or you can qualify 'member' in some way, e.g. 'this.member'.


Of course you must have meant this->member.
Jul 22 '05 #4
* Sharad Kala:

"Alf P. Steinbach" <al***@start.no> wrote in message
* Marc Schellens:
To give it that clue you can use a 'using' statement in class D,
or you can qualify 'member' in some way, e.g. 'this.member'.


Of course you must have meant this->member.


Thanks. I shall curse 4 million times before next compiling C#.

--
A: Because it messes up the order in which people normally read text.
Q: Why is it such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?
Jul 22 '05 #5

This thread has been closed and replies have been disabled. Please start a new discussion.

Similar topics

12
by: lawrence | last post by:
I have a string which I want to send to eval(). How can I test it ahead of time to make sure it is valid code? I don't want to send it to eval and get parse errors. I want to do something like...
16
by: siliconmike | last post by:
Hi, I'm looking for a reliable script that would connect to a host and somehow determine whether an email address is valid. since getmxrr() only gets the mx records.. Links/pointers ? Mike
1
by: Anna | last post by:
Hi all. I have probably a rather stupid question. If there is an HTML document, XML-formed using JTidy, is there any tool to convert it to valid XHTML? I.e. so that all the tags and attribute...
7
by: JR | last post by:
Hey all, I have read part seven of the FAQ and searched for an answer but can not seem to find one. I am trying to do the all too common verify the data type with CIN. The code from the FAQ...
23
by: James Aguilar | last post by:
Someone showed me something today that I didn't understand. This doesn't seem like it should be valid C++. Specifically, I don't understand how the commas are accepted after the function...
3
by: Chris | last post by:
Hi, In C# I tried to save a file from a generated file name. Just before launching the dialog I check for a valid file name to be sure. There for I used the method ValidateNames from the save...
0
by: QA | last post by:
I am using a Business Scorecard Accelarator in a Sharepoint Portal 2003 using SQL Server 2005 I am getting the following error: Error,5/7/2005 10:50:14 AM,580,AUE1\Administrator,"Specified cast is...
1
by: Robert Morgan | last post by:
|I'm trying to run a query on a database using php and postgres functions ||<?php db_connect(); $stat = pg_exec($connstr,"SELECT WSID from tblWorkstation "); while ($row = pg_fetch_rows($stat))...
1
by: illegal.prime | last post by:
Hey all, I have an app, that could take two numbers of any type of numerical type int, long, double, float, uint, ulong, etc. I want to check that the numbers are part of a range that I consider...
10
by: SpreadTooThin | last post by:
Hi I'm writing a python script that creates directories from user input. Sometimes the user inputs characters that aren't valid characters for a file or directory name. Here are the characters...
0
by: ryjfgjl | last post by:
ExcelToDatabase: batch import excel into database automatically...
0
isladogs
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...
0
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...
0
by: ArrayDB | last post by:
The error message I've encountered is; ERROR:root:Error generating model response: exception: access violation writing 0x0000000000005140, which seems to be indicative of an access violation...
1
by: PapaRatzi | last post by:
Hello, I am teaching myself MS Access forms design and Visual Basic. I've created a table to capture a list of Top 30 singles and forms to capture new entries. The final step is a form (unbound)...
1
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...
1
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....
0
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
0
by: Faith0G | last post by:
I am starting a new it consulting business and it's been a while since I setup a new website. Is wordpress still the best web based software for hosting a 5 page website? The webpages will be...

By using Bytes.com and it's services, you agree to our Privacy Policy and Terms of Use.

To disable or enable advertisements and analytics tracking please visit the manage ads & tracking page.