Is there a concept of function declaration in powershell?

Question

PowerShell

Good afternoon everyone, does powershell have the concept of a function declaration, as in C++, for example, or does a function have to be defined before it is used in code or imported from a module.
Let me explain what I mean. in si you could do something like

//Заголовок
int foo( int a,int b); //объявление функции
int main()
{
      //основной код
}
int foo(int a,int b) //определение функции
{
     return a+b
}

Answer 1

No.