char - Why does this code with '1234' compile in C++?

Question

Why does this compile:

char ch = '1234'; //no error

But not anything more than 4 chars :

char ch = '12345'; //error: Too many chars in constant

(Yes I know ' ' is used for one char and " " is for strings; I was just experimenting)

Does this have anything to do with the fact that chars are represented using ASCII numbers?

Answer 1

C++ has something called "multicharacter literals". '1234' is an example of one. They have type int, and it is implementation-defined what value they have and how many characters they can contain.

It's nothing directly to do with the fact that characters are represented as integers, but chances are good that in your implementation the value of '1234' is defined to be either:

'1' + 256 * '2' + 256 * 256 * '3' + 256 * 256 * 256 * '4'

or:

'4' + 256 * '3' + 256 * 256 * '2' + 256 * 256 * 256 * '1'