Python and checked exceptions

[Kay Schluehr]

A new cookbook recipe suggesting two decorators @throws and @catches
for treatment of checked exceptions in Python:

http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/498131

This might be of practical interest for some and theoretical interest
for others - in particular those who know checked ex as a language
feature of Java.

Regards,
Kay

[Peter Otten]

Re: Python and checked exceptions

Kay Schluehr wrote:

A new cookbook recipe suggesting two decorators @throws and @catches
for treatment of checked exceptions in Python:
>

http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/498131

>
This might be of practical interest for some and theoretical interest
for others - in particular those who know checked ex as a language
feature of Java.

Probably not what you wanted:

>>test()

Raises UncheckedExcept ionError(except ions.ZeroDivisi onError) -OK
Raises ZeroDivisionErr or -OK
Traceback (most recent call last):
File "<stdin>", line 1, in ?
File "checked_except ions.py", line 134, in test
test4(3,2)
UnboundLocalErr or: local variable 'test4' referenced before assignment

Peter

[Lawrence D'Oliveiro]

Re: Python and checked exceptions

In message <1159009493.872 015.33880@d34g2 000cwd.googlegr oups.com>, Kay
Schluehr wrote:

A new cookbook recipe suggesting two decorators @throws and @catches
for treatment of checked exceptions in Python:
>

http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/498131

>
This might be of practical interest for some and theoretical interest
for others - in particular those who know checked ex as a language
feature of Java.

The trouble with having to declare every possible exception that a function
might throw is that it rapidly turns into a complete mess. That's why such
declarations are optional in C++, and only semi-mandatory in Java.

[Diez B. Roggisch]

Re: Python and checked exceptions

>This might be of practical interest for some and theoretical interest
>for others - in particular those who know checked ex as a language
>feature of Java.

>
The trouble with having to declare every possible exception that a
function might throw is that it rapidly turns into a complete mess. That's
why such declarations are optional in C++, and only semi-mandatory in
Java.

I agree with you that they are a mess, and I usually wrap them
RuntimeExceptio ns.

Why do you call them semi-mandatory?

diez

[Kay Schluehr]

Re: Python and checked exceptions

Peter Otten wrote:

Kay Schluehr wrote:
>

A new cookbook recipe suggesting two decorators @throws and @catches
for treatment of checked exceptions in Python:

http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/498131

This might be of practical interest for some and theoretical interest
for others - in particular those who know checked ex as a language
feature of Java.

>
Probably not what you wanted:
>

>test()

Raises UncheckedExcept ionError(except ions.ZeroDivisi onError) -OK
Raises ZeroDivisionErr or -OK
Traceback (most recent call last):
File "<stdin>", line 1, in ?
File "checked_except ions.py", line 134, in test
test4(3,2)
UnboundLocalErr or: local variable 'test4' referenced before assignment
>
Peter

Thanks, I fixed this.

Kay