[Python-ideas] csv.DictReader could handle headers more intelligently.

Fri Jan 25 04:20:23 CET 2013

On 01/24/2013 02:47 AM, Mark Hackett wrote:
> On Thursday 24 Jan 2013, Steven D'Aprano wrote:
>>>> I'm not sure this behavior merits the all-caps "AS EXPECTED" label.
>>> It's not terribly surprising once you sit down and think about it, but
>>> it's certainly at least a little unexpected to me that data is being
>>> thrown away with no notice. It's unusual for errors to pass silently
>>> in python.
>>>> Yes, we should not forget that a CSV file is not a dict. Just because
>> DictReader is implemented with a dict as the storage, doesn't mean that it
>> should behave exactly like a dict in all things. Multiple columns with the
>> same name are legal in CSV, so there should be a reader for that
>> situation.
>>>> But just because it's reading a csv file, we shouldn't change how a dictionary
> works if you add the same key again.

The proposal is not to change how a dict works, but what the proper 
response is for DictReader when a duplicate key is found.
~Ethan~