[Python-ideas] CSV api with conversion

[MRAB]

Bruce Leban wrote:
> Sure I could do that. I just this think if you're making a convenience 
> function like this you should strive to make it more convenient.  :-)
> 
If you're passing in 'int' as a conversion function then it should do
what 'int' does, which is to raise an exception.

I could quote the Zen of Python:

     Errors should never pass silently.
     Unless explicitly silenced.

It shouldn't be so convenient that it leads to sloppy coding. :-)

> --- Bruce
> (via android)
> 
>> On Apr 14, 2010 4:03 PM, "MRAB" <python at mrabarnett.plus.com 
>> <mailto:python at mrabarnett.plus.com>> wrote:
>>
>> Bruce Leban wrote:
>> >
>> > If you do this, you'll probably want to support mapping empty 
>> values. That is...
>>
>> The actual values read from the CSV file are strings and you're passing
>> them to functions:
>>
>>    int("1"), str("")
>>    int(""), str("2")
>>
>> If you want it to return a default value instead of raising an exception
>> on an empty field then you should pass a conversion function which does
>> that, for example:
>>
>>    def int_or_none(field):
>>        if field.strip():
>>           return int(field)
>>        else:
>>           return None
>>