Beginners

by admin
Welcome -- read before posting!
 
Welcome to the beginner's forum in C++.com! In this forum, users can to talk about any topic related to C++ for non-expert audiences. Feel free to participate...
[2 replies] Last: How To Answer Questions in a Helpful Way Be gentle. Problem-relat... (by admin)
by closed account 3A4iE3v7
Console Closing Down (1,2,3,4,5,6,7)
 
Hi, i am new to C++ and have just written my "Hello World" program. It worked all right but the console/cmd closes down instantly. If you tell me why it is clos...
[120 replies] Last: It displayed "Hello world" after you pressed Enter. int c is a ... (by Duthomhas)
by Mif
C programming. "Using #include inside array initialization"
 
Hello again.. I just want to know if the syntax bellow is valid.. I tried to initialize an array with a file instead where are defined some assets, but I get an...
[16 replies] Last: Yup.. it is. Okay this being said.. I'll pass over and mark this as so... (by Mif)
by ElusiveTau
Logging Wrong Line Number
 
I'm working with C++17 or prior. I'm writing a custom logger class (I don't have access to a logging library) and have an issue with the following use case. ...
[5 replies] Last: [quote=kigar64551]#ifdef CUSTOM_LOGGER #ifdef CUSTOM_LOGGER # define ... (by ElusiveTau)
by Ch1156
Is my understanding of pointers correct?
 
So I've been studying pointers and really trying to learn how to use them and how they work, and I feel like I completely understand their use cases now. I...
[19 replies] Last: I have just discovered that [ ] can be applied to type constructors ... (by TheIdeasMan)
by ElusiveTau
Getter for enum member returns a copy of enum?
 
I came across something non-intuitive, found a solution, but don't fully understand why the solution works. #include <iostream> using namespace std; enum ...
[11 replies] Last: My view with regard to interface and not needing setters and maybe nee... (by TheIdeasMan)
by Jonathan100
Using of voltile qualifier
 
Hi, Where should i use volatile keyword in cpp? I wrote a code in cpp which communicating with a memory mapped IO (MMIO) - specifically a IP core with base add...
[3 replies] Last: [quote=ElusiveTau]In multi-threaded applications, volatile can be used... (by Peter87)
by Ch1156
Using std::variant to reduce getter and setter clutter
 
I'm experimenting with new ways to reduce code bloat, and one of my biggest gripes is always having to create two different functions for one variable, so my so...
[18 replies] Last: Just on the C++ language, IMO it does seem a pain that things take so ... (by TheIdeasMan)
by Coubarrie
C++ and the Government
 
Could anyone care to comment on the following? https://www.theregister.com/2024/11/08/the_us_government_wants_developers/
[4 replies] Last: you use what the government tells you to if you work for them, directl... (by jonnin)
by Ch1156
Is this how you do object chaining?
 
Im learning about object chaining and im wondering if im doing it correctly. #include <iostream> #include <print> #include <string> #include <vector> ...
[9 replies] Last: Thank you for all the replies! That seems like a straight forward conc... (by Ch1156)
by nowy20180820
Programming math - polynomial class
 
How to write templated polynomial class I would like to have overloaded operators like + -(unary,binary) * Here we can have school multiplication or...
[8 replies] Last: A wouldn't make this a template, unless you need it to work with float... (by dhayden)
by Jonathan100
stack and heap
 
Hi, I have some programming concepts question: Why is stack (in context of stack and heap) considered LIFO (last in first out)? The last time i checke...
[9 replies] Last: What question, exactly? Weren't here plenty of explanations ("solution... (by keskiverto)
by zzzhhh
Should the subscript "opt" be dropped in the definition of "array of N T" in the standard?
 
This is the definitive syntax of "array of N T" in C++ Standard https://eel.is/c++draft/dcl.array#1 : D1 [ constant-expression_opt ] ... I think the subs...
[3 replies] Last: Hi Is it because the array bound may be omitted when there are initia... (by TheIdeasMan)
by zzzhhh
Where is const mandated in the Standard when binding an lvalue reference to an rvalue?
 
I'm reading the part of the Standard about initializing an lvalue reference from an rvalue (https://eel.is/c++draft/dcl.init.ref#5.3 ). I know a reference to co...
[1 reply] : I don't think I've ever actually read the standard in over 30 years of... (by seeplus)
by zzzhhh
Which item stipulates that A() is a prvalue?
 
class A { ... }; A(); This webpage lists all possible forms of prvalue expressions: https://en.cppreference.com/w/cpp/language/value_cat...
[2 replies] Last: I believe that A() is a function-style cast expression and is covered ... (by mbozzi)
by ElusiveTau
How to compare int class template value?
 
I'm aware I should use std::string but this is question is about using template specialization a specific way. I'm learning about template specialization and ...
[2 replies] Last: 2. That's a good point. Only up to MAX_CSTR_SIZE-1 bytes will be copie... (by ElusiveTau)
by ElusiveTau
Template errors creating a map<int,std::thread> using map::emplace
 
I created a class to try out std::lock_guard. The first function, UnsafeExample compiles and runs fine. The second example, SafeExample does not compile a...
[2 replies] Last: Thanks Peter. That was it. 1. std::ref(coutMutex) was necessary, for ... (by ElusiveTau)
by ElusiveTau
How to initialize base class member with subclass member?
 
I'm working with code where CustomThreadApi is not modifiable. CustomThreadApi has a ctor that takes a const char* . I would like to assign MyThreadClass.Nam...
[2 replies] Last: baseClassBuff is unnecessary. I can just reuse MyThreadClass.Name .... (by ElusiveTau)
by Cyclone
Removing double quotes from Cstring
 
Hi, sorry its late... I am trying to do a few things with strings. - I need to remove double quotes from a users input - Then the string needs to be divide i...
[8 replies] Last: You only get double quotes if some component of the filename path has ... (by Duthomhas)
by Shervan360
Are these ternary operators the same?
 
Hello, What are the differences between these? #include <iostream> int main() { int a = 18, b = 44, total = 0, total2 = 0; total +=...
[8 replies] Last: I think some chips have a way to test a single bit but in general, I d... (by jonnin)