Josiah Carlson a écrit :
Pierre Barbier de Reuille <pierre.barbier@cirad.fr> wrote:
Well, I want to come back on a point that wasn't discussed. I only found one positive comment here : http://mail.python.org/pipermail/python-dev/2005-August/055775.html
You apparently haven't been reading python-dev for around 36 hours, because there have been over a dozen positive comments in regards to str.partition().
Well, I wasn't criticizing the overall idea of str.partition, which I found very useful ! I'm just discussing one particular idea, which is to avoid the use of exceptions.
Raymond Hettinger wrote:
* The function always succeeds unless the separator argument is not a string type or is an empty string. So, a typical call doesn't have to be wrapped in a try-suite for normal usage.
Well, I wonder if it's so good ! Almost all the use case I find would require something like:
head, sep, tail = s.partition(t) if sep: do something else: do something else
Why don't you pause for a second and read Raymond's post here: http://mail.python.org/pipermail/python-dev/2005-August/055781.html
In that email there is a listing of standard library translations from str.find to str.partition, and in every case, it is improved. If you believe that str.index would be better used, take a moment and do a few translations of the sections provided and compare them with the str.partition examples.
Well, what it does is exactly what I tought, you can express most of the use-cases of partition with: head, sep, tail = s.partition(sep) if not sep: #do something when it does not work else: #do something when it works And I propose to replace it by : try: head, sep, tail = s.partition(sep) # do something when it works except SeparatorError: # do something when it does not work What I'm talking about is consistency. In most cases in Python, or at least AFAIU, error testing is avoided and exception launching is preferred mainly for efficiency reasons. So my question remains: why prefer for that specific method returning an "error" value (i.e. an empty separator) against an exception ? Pierre -- Pierre Barbier de Reuille INRA - UMR Cirad/Inra/Cnrs/Univ.MontpellierII AMAP Botanique et Bio-informatique de l'Architecture des Plantes TA40/PSII, Boulevard de la Lironde 34398 MONTPELLIER CEDEX 5, France tel : (33) 4 67 61 65 77 fax : (33) 4 67 61 56 68