Like dividing by zero

there's stack unwinding

etc

there's stack unwinding

Then

the reason why exceptions are better is that they are clearer

Exception provide a better mechanism to handle the error

Exception provide a better mechanism to handle the error

which one?

which one?

Try catch

https://stackoverflow.com/questions/2350489/how-to-catch-segmentation-fault-in-linux

works with sigsev too

Try catch

Because they are clear

the reason why exceptions are better is that they are clearer

yep

thats the reason why exceptions are better

You don't wanna fill your program with if else

but (IMHO) the reason why array is better than c-style arrays is that they have iterators, strong typing, move semantics, and they have some dank utilities

You don't wanna fill your program with if else

Not relevant to the question "why are exceptions better than sigsevs?"

But if you wanna have a variable lenght (not resizable) you better use the style array

which array?

the c style array or the C++ style array?

the c style array or the C++ style array?

Yup

Yup

the c style array xor the c++ style array?

You can't do this int a = 8; std::array<int, a> x;

with constexpr you can

with constexpr you can

You cant with const

but you cannot do that with C style arrays as well, btw

You cant with const

Yeah :D

but you cannot do that with C style arrays as well, btw

int a; int b[a]; is valid C11 but invalid C++

int a; int b[a]; is valid C11 but invalid C++

Yes it is🤔

(in C++, we use a cheap workaround where we declare an int b[1];)

Yes it is🤔

so your point is kinda invalid

Hmmm

You answered yourself

And if i want to insert contacts everytime i want?

Frens, another question, that I am 100% sure I know the answer to. is there a way to have a template that can take any arbitrary class? For example, say I have: Class1 a; Class2 b; Class3 c; And I want to be able to have a driver: BaseClass base; But I want to be able to pass in Class1, and Class2 into the constructor of the base class without having to specifically state: BaseClass(Class1 A, Class2 B); I would love to do: template <class A, class B> BaseClass { BaseClass(A &class1, B &class2); }; However, the problem with this is I won't know what class1 or class2, or have any access to any of their functions. Is there a way I can do this? Or do I have to specifically state in the constructor a specific class?

Sorry that it is so long!

And if i want to insert contacts everytime i want?

You use a big enough array. Or you just read the other answers

but (IMHO) the reason why array is better than c-style arrays is that they have iterators, strong typing, move semantics, and they have some dank utilities

- std:;array offers value semantics instead of decaying to a pointer, so you can easy return or copy it. - std::array does support Random Access Iterators. (C style arrays support Bidirectional Iterators at least) But I doubt std::array would benefit from move semantics

Frens, another question, that I am 100% sure I know the answer to. is there a way to have a template that can take any arbitrary class? For example, say I have: Class1 a; Class2 b; Class3 c; And I want to be able to have a driver: BaseClass base; But I want to be able to pass in Class1, and Class2 into the constructor of the base class without having to specifically state: BaseClass(Class1 A, Class2 B); I would love to do: template <class A, class B> BaseClass { BaseClass(A &class1, B &class2); }; However, the problem with this is I won't know what class1 or class2, or have any access to any of their functions. Is there a way I can do this? Or do I have to specifically state in the constructor a specific class?

You can call any function. If the function does not exist your compiler will tell you. Otherwise you can look into SFINAE to get more information

You can call any function. If the function does not exist your compiler will tell you. Otherwise you can look into SFINAE to get more information

Actually, somehow it was working the entire time. Templates are magic.

However, now I am trying to figure out how to combine any_cast with this.

Actually, somehow it was working the entire time. Templates are magic.

If the types you pass define the funcitons you call, there is no issue. Try passing something like int or void* and chances increase it will fail

If the types you pass define the funcitons you call, there is no issue. Try passing something like int or void* and chances increase it will fail

so what if I do this: map.emplace("setValue",&A::setValue); What is my any_cast going to look like? I tried: std::any_cast<void(*)(int)>(mapIter->second)(newVal); This compiles, but it throws a bad_any_cast exception. So what should I be casting it to? I'm assuming void(*) is incorrect here.

so what if I do this: map.emplace("setValue",&A::setValue); What is my any_cast going to look like? I tried: std::any_cast<void(*)(int)>(mapIter->second)(newVal); This compiles, but it throws a bad_any_cast exception. So what should I be casting it to? I'm assuming void(*) is incorrect here.

because the type is not the same. You take a member function, which is probably of type void(A::*)(int)

because the type is not the same. You take a member function, which is probably of type void(A::*)(int)

that is what I did haha, problem now is now I get the compiler error that I must use .* or ->* to call pointer-to-member function. No idea what to do with that now. And I am not sure why I need to do that because it is my map that belongs to the class.

that is what I did haha, problem now is now I get the compiler error that I must use .* or ->* to call pointer-to-member function. No idea what to do with that now. And I am not sure why I need to do that because it is my map that belongs to the class.

What are you actually trying to do? Pretty sure that is not a good solution this works though https://godbolt.org/z/NbF9Ws

What are you actually trying to do? Pretty sure that is not a good solution this works though https://godbolt.org/z/NbF9Ws

Honestly, you are correct. This is a bad solution what I am trying to do is this: template<class A, class B> class BaseClass { public: BaseClase(const A &class1, const B &class2) { bindThem(); } void setValue(int newVal) { auto mapIter = map.find("setVal"); std::any_cast<void(A::*)(int)>(mapIter->second)(newVal); } void bindThem() { map.emplace("setVal",&A::setValue); } private: std::unordered_map<std::string,std::any> map; }

the EASIER, and best way, would be to create two private class variables and then call: classA.setValue(newVal); classB.setValue(newVal);

I am just trying to do something else for fun and making it harder on myself because that's how we learn about this stuff.

Hi guys

Hi friends

Honestly, you are correct. This is a bad solution what I am trying to do is this: template<class A, class B> class BaseClass { public: BaseClase(const A &class1, const B &class2) { bindThem(); } void setValue(int newVal) { auto mapIter = map.find("setVal"); std::any_cast<void(A::*)(int)>(mapIter->second)(newVal); } void bindThem() { map.emplace("setVal",&A::setValue); } private: std::unordered_map<std::string,std::any> map; }

Still, why would you want to do this? Your setValue does not work, you need an object to call the member function on. What problem are you trying to solve that this does not solve? template <class A> class Base { A & a; public: Base(A & a) : a(a) {} void set(int x) { a.setA(x); } }; You can use it like this A a; Base<A> ba{a}; ba.set(3);

.

what does void (*)(int);and A::* mean?

function pointers

hello guys? my name is fit. i need some help from you guys.. i have a project for my subject and its c++ language.. about insert how many information and then calculate it. the problem im having right now is on the picture as u can see the spacing is not right cause i dont know how to manage it. i use while to call for the output. ========================= does any of u guys know how to let the output stay on the same line eventhough the information inserted too short or too long? thanks. sorry for bad english and no0b coding cause i only learn the basic.

here is some of the code about the output..

Still, why would you want to do this? Your setValue does not work, you need an object to call the member function on. What problem are you trying to solve that this does not solve? template <class A> class Base { A & a; public: Base(A & a) : a(a) {} void set(int x) { a.setA(x); } }; You can use it like this A a; Base<A> ba{a}; ba.set(3);

I am trying to do this because I am trying to save myself from doing class1.set(5) class2.set(5) class3.set(5) Whenever something in a UI happens. It would be much cleaner to have to just have a base class that acts as driver and modifies the code if they depend on each other. Say one class is an OpenGL setter function, one class is a textBox that waits for input, and another is a slider that adjusts color. And that slider affects the openGL call and the input of the text box. And maybe I have more than one slider. See the issue now? Everytime I have to make an update I have to update those things within a code manually. This can get ugly and complex really fast. So I am trying to simplify things into just one base that can handle all of this when an update happens. This class will only know of the getter and setter functions. That's it. So I am trying to wrap them into a class without having to do: update (int value) { ui->mySlider->setValue(value); ui->myTextBox->setValue(value); GLClass->setValue(value); ... // More objects to set } Instead it would be nice to just modify what is necessary. update(ui->mySlider, GLClass,value) { BaseClass<ui->mySlider,GLClass> base; base->setValue(value); }

Hello

@linuxer4fun Is that you first message?!

dunno

its well possible

thank you all

hi

hi I have a variable (x), and I want to store several data in one variable. How can I do this in C language?

you can't

(you cannot easily atleast)

hi I have a variable (x), and I want to store several data in one variable. How can I do this in C language?

Array

thats not the same

hi I have a variable (x), and I want to store several data in one variable. How can I do this in C language?

You can do it with pointers

no

Order in one variable For example a variable variable named ... x = 33; ... x = 66; ... x = 90; But can data be saved and can be called and stored

those are separate variables next to eachother

Order in one variable For example a variable variable named ... x = 33; ... x = 66; ... x = 90; But can data be saved and can be called and stored

impossible

those are separate variables next to eachother

int *p; p++; content 1 p++; content 2 . . And so on

thats not one variable

One variable

those are multiple variables

but one pointer

thats not one variable

Define the variable

int *p; p++; content 1 p++; content 2 . . And so on

You can just loop it

How can I not do it?