Re: exception on string (out_of_range)

From:

eric <cneric12lin0@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Thu, 7 Jul 2011 10:05:14 -0700 (PDT)

Message-ID:

<ca4e8e2c-4f02-4a1c-a47b-9f8c9deb98dd@e21g2000vbz.googlegroups.com>

On Jul 7, 9:53 am, F=D6LDY Lajos <fo...@rmki.kfki.hu> wrote:

On Thu, 7 Jul 2011, eric wrote:

On Jul 7, 8:33 am, F=D6LDY Lajos <fo...@rmki.kfki.hu> wrote:

On Thu, 7 Jul 2011, eric wrote:

Dear Advanced C++ programers:

from book (c++ cookbook), chapter 4, section 3: Storing Strings in=

Sequence
---------
#include <iostream>
#include <vector>
#include <exception>

using namespace std;

int main() {

char carr[] = {'a', 'b', 'c', 'd', 'e'};

cout << carr[100000] << '\n'; // Whoops, who knows what's g=

oing

/ to happen

vector<char> v;
v.push_back('a');
v.push_back('b');
v.push_back('c');
v.push_back('d');
v.push_back('e');

try {
cout << v.at(10000) << '\n'; // at checks bounds and throw=

} catch(out_of_range& e) { // out_of_range if it's inv=

alid

cerr << e.what() << '\n';
}
}
---------------------------------------------------------------------=

my g++ response
-----------------
eric@eric-laptop:~/cppcookbook/download$ g++ 4-7.cpp
4-7.cpp: In function ?int main()?:
4-7.cpp:20:11: error: expected type-specifier before ?out_of_range?
4-7.cpp:20:23: error: expected ?)? before ?&? token
4-7.cpp:20:23: error: expected ?{? before ?&? token
4-7.cpp:20:25: error: ?e? was not declared in this scope
4-7.cpp:20:26: error: expected ?;? before ?)? token
---------------------------------------------------------------------=

----------------

the code can be download from
http://examples.oreilly.com/9780596007614/
that mean it was tested success in some platform(vc++ in xp), so
please help, thanks a lot in advance, Eric

Try:

...
} catch(exception& e) { // out_of_range if it's inv=

alid

...

regards,
Lajos

-----------------------------------------------------------------------=

----------------------------

Thanks both Lajos and Mike Doubez's suggestions , and it can compile
now by following your suggestion
but, it did not run as expected
-----------
eric@eric-laptop:~/cppcookbook/ch4$ g++ Example4-7.cpp
eric@eric-laptop:~/cppcookbook/ch4$ ./a.out
Segmentation fault
---------------------------------------------------------
Do you know why it didn't go through the catch of my program rather
than through compiler(or operationSystem)'s?
Thanks your help a lot in advance, Eric

carr[100000] may be too far off. Try with carr[10] and v.at(10).

regards,
Lajos

yes, carr[100000]
so by the doc of stdexcept
http://www.cplusplus.com/reference/std/stdexcept/out_of_range/
I tried 2 additional errors
length_error
range_error

but result is still (Segmentation fault)
Do you know exactly which error(exception) my (carr[100000]) cause?

Eric