String array

[Mark S.]

Hi,
let's say I have following array of strings:
string s[] = { "This ", "is ", "a ", "very strange test." };

Am I correct in my line of thought that since each element somehow has a
size of 4 and the total size of the array is 16, I can use
sizeof(s)/sizeof*(s) as I would with other built-in types?
Or is there something else to consider? And why is the size of the
string always 4?

Kind regards
Mark

 

[Bart van Ingen Schenau]

Hi,
let's say I have following array of strings:
string s[] = { "This ", "is ", "a ", "very strange test." };

Am I correct in my line of thought that since each element somehow has a
size of 4 and the total size of the array is 16, I can use
sizeof(s)/sizeof*(s) as I would with other built-in types?

Yes, you can use the sizeof/sizeof method on any array, regardless of
the base type. It even works for non-built-in types (as you already
noticed, because std::string is technically also a user-defined type).

Or is there something else to consider? And why is the size of the
string always 4?

sizeof(std::string) only gives you the amount of bookkeeping data that
std::string uses. The actual string content is stored in a separate
buffer, which is dynamically allocated.

Kind regards
        Mark

Bart v Ingen Schenau

 

[Mark S.]

Hi,
let's say I have following array of strings:
string s[] = { "This ", "is ", "a ", "very strange test." };

Am I correct in my line of thought that since each element somehow has a
size of 4 and the total size of the array is 16, I can use
sizeof(s)/sizeof*(s) as I would with other built-in types?

Yes, you can use the sizeof/sizeof method on any array, regardless of
the base type. It even works for non-built-in types (as you already
noticed, because std::string is technically also a user-defined type).

Or is there something else to consider? And why is the size of the
string always 4?

sizeof(std::string) only gives you the amount of bookkeeping data that
std::string uses. The actual string content is stored in a separate
buffer, which is dynamically allocated.

Kind regards
Mark

Bart v Ingen Schenau

Alright, thank you!

 

[Pascal J. Bourguignon]

Hi,
let's say I have following array of strings:
string s[] = { "This ", "is ", "a ", "very strange test." };

Am I correct in my line of thought that since each element somehow has
a size of 4 and the total size of the array is 16, I can use
sizeof(s)/sizeof*(s) as I would with other built-in types?
Or is there something else to consider? And why is the size of the
string always 4?

sizeof(std::string) is not always 4, it depends on the implementation.
It might be three long words (eg. 12 chars) or more, or less.