Re: Error and Exception chaining
On Tuesday, 13 December 2016 at 00:33:58 UTC, Yuxuan Shui wrote:
On Monday, 12 December 2016 at 22:35:22 UTC, Yuxuan Shui wrote:
On Monday, 12 December 2016 at 22:13:59 UTC, Ali Çehreli wrote:
On 12/12/2016 02:08 PM, Yuxuan Shui wrote:
> [...]
wrote:
>> [...]
Error.bypassedException
>> [...]
mechanism,
>> [...]
Error."
>> [...]
Exception,
>> [...]
otherwise
>> [...]
original
>> [...]
is the Error.
> [...]
Exception to
> [...]
Currently yes. Now this line in my versatile :o) program:
if (n >= errorIndex) {
Two Errors are chained:
Caught
TestError: 3
TestError: 4
However, there is the following ongoing thread claiming that
it was a wrong decision:
http://forum.dlang.org/post/o2n347$2i1g$1...@digitalmars.com
> [...]
From what I could graps from that much of documentation, yes,
it seems to be a bug.
I did some testing and bypassedException is null in 2.072.1,
but is not null in 2.070.2
Ali
The unwind process seem to stop one level too early, causing
language_specific_data to be different, causing
__dmd_personality_v0 to not chain exception into
.bypassException.
OK. I think I figured it out. catch(Error x) won't catch
TestException, so TestException 0,1,2 is not handled at main().
However TestError 3 (and TestExcepotion 4 which is chained to it)
is handled at main(). And dmd won't put Throwables that are
handled at different places together.
This behavior seems reasonable. So maybe this is actually a bug
is LDC?
Re: Error and Exception chaining
On Monday, 12 December 2016 at 22:35:22 UTC, Yuxuan Shui wrote:
On Monday, 12 December 2016 at 22:13:59 UTC, Ali Çehreli wrote:
On 12/12/2016 02:08 PM, Yuxuan Shui wrote:
> [...]
wrote:
>> [...]
Error.bypassedException
>> [...]
mechanism,
>> [...]
Error."
>> [...]
Exception,
>> [...]
otherwise
>> [...]
original
>> [...]
is the Error.
> [...]
Exception to
> [...]
Currently yes. Now this line in my versatile :o) program:
if (n >= errorIndex) {
Two Errors are chained:
Caught
TestError: 3
TestError: 4
However, there is the following ongoing thread claiming that
it was a wrong decision:
http://forum.dlang.org/post/o2n347$2i1g$1...@digitalmars.com
> [...]
From what I could graps from that much of documentation, yes,
it seems to be a bug.
I did some testing and bypassedException is null in 2.072.1,
but is not null in 2.070.2
Ali
The unwind process seem to stop one level too early, causing
language_specific_data to be different, causing
__dmd_personality_v0 to not chain exception into .bypassException.
Re: Error and Exception chaining
On Monday, 12 December 2016 at 22:13:59 UTC, Ali Çehreli wrote:
On 12/12/2016 02:08 PM, Yuxuan Shui wrote:
> [...]
wrote:
>> [...]
Error.bypassedException
>> [...]
mechanism,
>> [...]
Error."
>> [...]
Exception,
>> [...]
otherwise
>> [...]
original
>> [...]
is the Error.
> [...]
Exception to
> [...]
Currently yes. Now this line in my versatile :o) program:
if (n >= errorIndex) {
Two Errors are chained:
Caught
TestError: 3
TestError: 4
However, there is the following ongoing thread claiming that it
was a wrong decision:
http://forum.dlang.org/post/o2n347$2i1g$1...@digitalmars.com
> [...]
From what I could graps from that much of documentation, yes,
it seems to be a bug.
I did some testing and bypassedException is null in 2.072.1, but
is not null in 2.070.2
Ali
Re: Error and Exception chaining
On 12/12/2016 02:08 PM, Yuxuan Shui wrote:
> Thanks a lot for the explanation!
>
> On Monday, 12 December 2016 at 22:01:54 UTC, Ali Çehreli wrote:
>> (Note: Looks like there is a bug regarding Error.bypassedException
>> member. Would others please confirm.)
>>
>> On 12/12/2016 01:15 PM, Yuxuan Shui wrote:
>> > [...]
>> that Error
>> > [...]
>> vague, and I'm
>> > [...]
>>
>> You're referring to "[Errors] bypass the normal chaining mechanism,
>> such that the chain can only be caught by catching the first Error."
>> What it means is that an Error cannot be a collateral of an Exception,
>> hiding in its chain. So, when there is an Error that would otherwise
>> be a collateral of an Exception, you cannot catch the original
>> Exception. What is more importantly in-flight at that time is the Error.
>>
>
> But chaining Error to Error works just like chaining Exception to
> Exception?
Currently yes. Now this line in my versatile :o) program:
if (n >= errorIndex) {
Two Errors are chained:
Caught
TestError: 3
TestError: 4
However, there is the following ongoing thread claiming that it was a
wrong decision:
http://forum.dlang.org/post/o2n347$2i1g$1...@digitalmars.com
>> But bypassedException member of Error is always null. Bug?
>
> Did I just randomly found a bug?
From what I could graps from that much of documentation, yes, it seems
to be a bug.
Ali
Re: Error and Exception chaining
Thanks a lot for the explanation! On Monday, 12 December 2016 at 22:01:54 UTC, Ali Çehreli wrote: (Note: Looks like there is a bug regarding Error.bypassedException member. Would others please confirm.) On 12/12/2016 01:15 PM, Yuxuan Shui wrote: > [...] that Error > [...] vague, and I'm > [...] You're referring to "[Errors] bypass the normal chaining mechanism, such that the chain can only be caught by catching the first Error." What it means is that an Error cannot be a collateral of an Exception, hiding in its chain. So, when there is an Error that would otherwise be a collateral of an Exception, you cannot catch the original Exception. What is more importantly in-flight at that time is the Error. But chaining Error to Error works just like chaining Exception to Exception? But bypassedException member of Error is always null. Bug? Did I just randomly found a bug? Thank you, Ali
Error and Exception chaining
I read https://dlang.org/spec/statement.html, which told me that Error is different in the way it's chained. But that is pretty vague, and I'm still confused. Can someone explain that using examples? Thanks.
