Are there any special considerations when using friend functions and namespaces?
objid.h
#pragma once namespace FOO { typedef ULONGobjid_t;
class OBJID {FOO::objid_tm_objnum;
[Code] ....
My C++03 compiler is giving me the following error:
C:devDATALIBOBJID.cpp(42,14) : error (346) : member "FOO::OBJID::m_objnum" is inaccessible
Is this a compiler issue, or am I missing something here trying to use a friend function? If I don't put the OBJID class in a namespace, everything compiles fine.
class Character; class Village; class Character { public: //Functions void charGen(); //Character creation
[Code] .....
According to the Friendship and Inheritance tutorial [URL] ...., that code should work, but it doesn't. I am given an error: undefined reference to questsCompleted
Ran into something today that does not make sense:
This compiles: Code: int x = 5;
switch(x) { case 0: { int value = 5; } break;
[Code] ....
Ok so it doesn't like int value = 6 b/c of int value = 5 for case 0. However since the value in case 0 is declared within the brackets one would think it has case scope.
So I tried this:
Code: int x = 5; switch(x) { case 0: { int value = 5; } break;
[Code] ....
Now it doesn't like it b/c value has not been declared in case 1:. These two conditions cannot possibly be both true at the same time. You cannot disallow the declaration of value in case 1 b/c it interferes with value in case 0 and at the same time disallow me to use value from case 0 b/c it is not in scope. If it was not in scope then theoretically I should be able to declare value in case 1.
Both MSVS 2012 and 2013 exhibit the same behavior. I checked the standard and it is unclear on the matter.
I'm working through this neural network tutorial, unfortunately I get stuck trying to compile on line 28, saying "error: 'neuronNum' not declared in this scope." I seem to always get stuck on these kinds of errors, yet I don't understand because I though that the variable was declared and initialized within the for loop.
#include <iostream> #include <vector> using namespace std;
Are there any situations to explicitly use the scope resolution operator with global scope? I can imagine a situation like:
#include <cmath> class IntWrapper{ public: IntWrapper& pow(char); IntWrapper(char); private: int m_int;
[Code] ....
But then I would think that the writer should have used a different name, and that using the scope resolution operator in the constructor body is still pointless...
Some coding standards document to follow for naming a variable, functions and using braces for if etc and other important standards i have to follow while writing the code. Right now in a hurry to finish the program i am naming a variable what ever comes to mind which is creating a lot of problems for me.
Write a function write with variable number of arguments that takes a string first argument followed by any number of arguments of type double and prints on the screen a string formatted by the rules described below. The first argument may contain formats in curly braces of the form {index[:specifier]}, where the square brackets show optional parts (this is :specifier may be missing), and index is the sequence number of an argument of type double (starting from sequence number 0).
Rules for formatting: In the printed string the curly brackets and their content will be replaced by the argument with the given index, formatted according to the given format specifier. If the format specifier is missing, the argument will be printed with its default format. For example:
write("The number {0} is greater than {1}.", 5, -3); will print The number 5 is greater than -3.
write("There are no format specifiers here."); will print There are no format specifiers here.
The format specifiers and their meanings are listed in the following table
Specifier MeaningFormat Output for 1.62 Output for 2.0 none default {0}1.62 2 ccurrency{0:c}$1.62 $2.00 escientific{0:e}1.620000e+000 2.000000e+000 ffixed point{0:f}1.620000 2.000000 iround to int{0:i}2 2
Limitations: You may limit the maximum number of arguments your function can process to a certain value, for example 10.
Suggested extensions: -Add an optional alignment specification in the format , e.g., make the format of the form {index[,alignment][:specifier]}, where alignment is an integer specifying the width of the field in which the corresponding argument will be printed. If alignment is positive, align to the right, if it is negative, align to the left. -Accept an optional integer after the specifier letter, specifying the required precision in the output. For example, {0:f2} will print the number 1.6234 as 1.62, but {0:f5} will print it as 1.62340.
So I have a class object that contains the private member variable spot and the public member function MoveLock. Within MoveLock, is a member variable called numbers that holds the place where a user is on a "lock knob". Now, what I'm trying to accomplish is that whenever the user turns the "knob" in the wrong direction, the position is updated with that current numbers so that the clicks needed to unlock the first state is also updated. But I get these errors:
Error E2096 C:Users...switchtest.cpp 34: Illegal structure operation in function main() Error E2294 C:Users...switchtest.cpp 39: Structure required on left side of . or .* in function main()
Ultimately, what I have in main() is a piece of what I'm going to implement in a class member function. I'm also thinking about moving the if else statements out of the for and creating a second one for the else portion.
Ok so when the program runs the first function the data is stored and displayed in the file. The second function is supposed to read the name entered, compare it to the ones in the file then take the price with it BUT I seem to have done something wrong when reading the files (or maybe it has to do with the global function I'm not sure). Here's parts of the code :
I can't provide a generic implementation of the << operator, it depends on the specific types of T. So how do I specialize the operator for a specific type T ?
Am trying to write table object into file. Here's the source code
.hpp file
class Table { private: int table_no; std::string table_type; bool engaged; std::time_t start_time; double total_sec;
[Code] ....
When i compile the above code i get the following error...
table.hpp: In function ‘std::ifstream& operator>>(std::ifstream&, Table&)’: table.hpp:19:7: error: ‘int Table::table_no’ is private table.cpp:91:12: error: within this context table.hpp:20:15: error: ‘std::string Table::table_type’ is private table.cpp:92:12: error: within this context ...........
#include <iostream> using namespace std; template <typename T> class max_vector { private: T* elemente; int lungime;
[Code] ....
The purpose of this program is to overload two different operators one inside the class, and the other one outside using friend. The problem is that i get 1 error at the '*' one.
I want to overload prefix and postfix increment(++) operators with friend function. I also have to use the constructors for this. How can I do this? in C++
I need understanding this block of code, particularly this line : *getLeftChild() { return this - _child; }
Code:
public class UpperNode { BOX _box; int _child; FORCEINLINE UpperNode *getLeftChild() { return this - _child; } ... };
Here I have this function:
Code: void UpperNode::visulization(int level) { if (isLeaf()) _box.visulization(); else if ((level > 0)) {
[Code] .....
It also makes calls for "getLeftChild()";
But I see that getLeftChild expects function pointer, and I absolutely have no clue where "this" comes from inside function body.
(return this - _child) - "this" has to be integer.
Or, if we gave pointer, and "this" is referring to some UpperNode, then I can't understand to which one, I have no UpperNode array defined or something. So if this functions is actually scaling pointer address, then scaling where to? I could comprehend it, if I had some array of UpperNodes, but not just class. I have UpperNodes array defined in other friendly class, but don't think they are related .....
