Tutorial - section 8.5 -- User Defined Execptions?

[Colin J. Williams]

user at domain.invalid wrote:

>  From the python documentation tutorial, section 8.5
> +++++++++++++++++++++++++++++++++++=
>  >>> class MyError:
> ...     def __init__(self, value):
> ...         self.value = value
> ...     def __str__(self):
> ...         return `self.value`
> ...
>  >>> try:
> ...     raise MyError(2*2)
> ... except MyError, e:
> ...     print 'My exception occurred, value:', e.value
> ...
> My exception occurred, value: 4
>  >>> raise MyError, 1
> Traceback (innermost last):
>    File "<stdin>", line 1
> __main__.MyError: 1
>
> +++++++++++++++++++++++++++++++++++=
>
> What do the back ticks in method "__str__" mean?

The back ticks, as in `self.value`,  are equivalent to repr(`self.value`).

ie. it provides the  ``official'' string representation of self.value.

Colin W.