15.07.2017, 18:33, "Chris Angelico" <rosuav@gmail.com>:
On Sun, Jul 16, 2017 at 10:12 AM, Jeff Walker <jeff.walker00@yandex.com> wrote:
The first problem is that there is no direct access to the components that make up the error in some of the standard Python exceptions.
>>> foo Traceback (most recent call last): File "<stdin>", line 1, in <module> NameError: name 'foo' is not defined
If you need access to the name, you must de-construct the error message. To get direct access to the name, it would need to be passed to the exception when raised. Why wasn't that done?
Because it normally isn't needed. Can you give an example of where NameError could legitimately be raised from multiple causes?
For me it generally occurs when users are using Python to hold their actual data. Python can be used as a data format in much the same way JSON or Yaml. And if the end user is familiar with Python, it provides many nice benefits over the alternatives. I tend to use it in this fashion a great deal, particularly for configuration information. In these case, it would be nice to be able access the 'participants' in the following exceptions: NameError (offending name) KeyError (collection, offending key) IndexError (collection, offending index) Jeff