Syntax explanation for "new" keyword for contracts in Solidity

Question

I am trying to understand the syntax of C c = new C();

I read the new keyword deploys, initializes state variables, runs the constructor, sets nonce to one, and returns address of new instance.

I read that a state variable a has a 0-ary public getter function a() that returns the value of a.

Questions:

1. What "is" the getter function of a contract?
2. Why does new act on the getter function?
3. In C c = new C(); why do we need the first C to define the variable?

Answer 1

A contract doesn't have a "getter" function. You could read C() as calling the contract's constructor (but the call isn't like regular functions).

The part new C() is the solidity syntax to deploy the C contract. The constructor accepts parameters so they can be passed like this new D(param1, param2, param3).

The requirement to declare the type returned in the assignment C c = ... is for security reasons. A few versions back solidity supported var c = ... but there were a few contracts with subtle bugs due to the wrong type deduced by the compiler.