Re: Error codes vs. exceptions

From:

Luca Risolia <luca.risolia@studio.unibo.it>

Newsgroups:

comp.lang.c++

Date:

Tue, 29 May 2012 22:42:05 +0200

Message-ID:

<jq3cap$kbj$3@speranza.aioe.org>

On 29/05/2012 06:15, mike3 wrote:

if(f(&x) != SUCCESS)
{ // handle error }
x += foo;

:)

Note how we can easily get LONG methods full of repeated code with
error codes (repeated error handlers to handle similar errors at
various function calls calling error-code-emitting functions, if one
wants to be more graceful than simply aborting with an error to the
next level up (which complicates what error codes a function can
return, since it can return its own codes in addition to those
returned by the functions below it, and those may have functions below
THEM, and so on...).). And who likes duplicated code? eww. This seems
a disadvantage of error codes.

As a note, an "exception" does not necessarily represents a failure. For
example, you can throw an exception to jump out of a recursive search
algorithm when the searched value is found:

void find_(Node* root, const char* str) {
     if (!root)
         return;
     if (!strcmp(str, root->str))
         throw root;
     find_(root->left, str);
     find_(root->right, str);
}

Node* find(Node* root, const char* str) {
     try {
         find_(root, str);
     } catch (Node* p) {
         return p;
     }
     throw not_found();
}