• Ben Hinkle (21/21) Aug 23 2004 I'm confused about what D calls errors and exceptions. Part of the chang...
• Sean Kelly (5/25) Aug 23 2004 I'm not sure. Though doFormat (a relatively new addition) throws an exc...
• Ben Hinkle (5/8) Aug 24 2004 holy shiskabobs - you're right. Well, looks like I'll send Walter anothe...
• Stewart Gordon (8/11) Aug 26 2004 Recoverable by whom - the app or the programmer?

Ben Hinkle <bhinkle4 juno.com> writes:

I'm confused about what D calls errors and exceptions. Part of the changes
that I've made to std.stream involve changing the Error subclasses to
Exception subclasses and I want to make sure this is the right thing to do.

Now, the doc http://www.digitalmars.com/d/errors.html talks about the class
Error and how it can be caught and handled. It also says all errors
subclass Error. So that makes me think Errors are recoverable. But then in
object.d the source code says:

// Recoverable errors
class Exception : Object ...
// Non-recoverable errors
class Error : Exception ...

I'm used to Exceptions being thrown/caught willy-nilly and Errors being
really serious problems that cause the app to abort. In D is it reversed?
If so then I'll back out my std.stream changes. Also I suggest some more
details in the errors.html doc about the different classes involved and
maybe even rename Exception to NonRecoverableError or something (or
vide-versa rename Error to NonRecoverableException).

Note I don't want to start a thread about the abstract concepts of
recoverable vs non-recoverable errors - I just want to know how those
concepts map to D.

-Ben

Sean Kelly <sean f4.ca> writes:

In article <cgcs6d$2ele$1 digitaldaemon.com>, Ben Hinkle says...
I'm confused about what D calls errors and exceptions. Part of the changes
that I've made to std.stream involve changing the Error subclasses to
Exception subclasses and I want to make sure this is the right thing to do.

Now, the doc http://www.digitalmars.com/d/errors.html talks about the class
Error and how it can be caught and handled. It also says all errors
subclass Error. So that makes me think Errors are recoverable. But then in
object.d the source code says:

// Recoverable errors
class Exception : Object ...
// Non-recoverable errors
class Error : Exception ...

I'm used to Exceptions being thrown/caught willy-nilly and Errors being
really serious problems that cause the app to abort. In D is it reversed?
If so then I'll back out my std.stream changes. Also I suggest some more
details in the errors.html doc about the different classes involved and
maybe even rename Exception to NonRecoverableError or something (or
vide-versa rename Error to NonRecoverableException).

Note I don't want to start a thread about the abstract concepts of
recoverable vs non-recoverable errors - I just want to know how those
concepts map to D.

I'm not sure.  Though doFormat (a relatively new addition) throws an exception
derived from Error, so I'm guessing that Walter currently considers Errors to be
recoverable no matter what the comment says.


Sean

"Ben Hinkle" <bhinkle mathworks.com> writes:

 I'm not sure.  Though doFormat (a relatively new addition) throws an

exception
 derived from Error, so I'm guessing that Walter currently considers Errors

to be
 recoverable no matter what the comment says.

holy shiskabobs - you're right. Well, looks like I'll send Walter another
version of std.stream with the old Error subclasses. Plus I'll start
updating all my code to use Error subclasses instead of Exceptions.

Stewart Gordon <smjg_1998 yahoo.com> writes:

Sean Kelly wrote:

<snip>
 I'm not sure.  Though doFormat (a relatively new addition) throws an exception
 derived from Error, so I'm guessing that Walter currently considers Errors to
be
 recoverable no matter what the comment says.

Recoverable by whom - the app or the programmer?

A FormatError strikes me as an indication of a bug.

Stewart.

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