Some questions again

Hallo,

I have a few question

1. Why return a reference?

2. What is the benefits of inline? From reading only I have gathered that it makes the program smaller and bigger. Faster and slower and so on.

3. When to use the keyword extern?

4. How do I assign something to a const class member variable?

Code:

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class Player{
public:
  Player(std::string n);
  ...
private:
  const std::string name;
};

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Thanks :)

Quote:

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Originally Posted by h3ro

1. Why return a reference?

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Because it avoids creating another copy of the object and it avoids using pointers for simple things. In short, it's more efficient.

Quote:

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2. What is the benefits of inline? From reading only I have gathered that it makes the program smaller and bigger. Faster and slower and so on.

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Inline makes the code faster, but can make the code bigger.

Quote:

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3. When to use the keyword extern?

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When you have a variable defined in a source file other than the one it's used in. Since you can't define something twice, and the compiler can't see the a variable in another source file, you must declare it as extern to tell the compiler it exists elsewhere.

Quote:

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4. How do I assign something to a const class member variable?

Code:

---

class Player{
public:
  Player(std::string n);
  ...
private:
  const std::string name;
};

---

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You can't. You must initialize it with the initialization list in the constructor.

Quote:

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1. Why return a reference?

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For function chaining, or to allow a member variable to be modified in a syntactically nice way.

Quote:

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2. What is the benefits of inline? From reading only I have gathered that it makes the program smaller and bigger. Faster and slower and so on.

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Indeed, the benefits depend on the context. It may avoid the overhead of a function call, but may introduce executable code bloat.

Quote:

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3. When to use the keyword extern?

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See Stroustrup's glossary on extern.

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4. How do I assign something to a const class member variable?

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You don't. You just initialise it in the constructor.

thanks:)

To your fourth question, you can assign a static constant data member in a class declaration:

Code:

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class Foo
{
public:
  static const int ARRAY_SIZE = 10;
....

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But I may of mis-read what you meant ;)