Commit f704e485 authored by Andrew M. Kuchling's avatar Andrew M. Kuchling

Add PEP305 section

parent acec26a5
......@@ -833,6 +833,56 @@ Implemented by Just van~Rossum.
\end{seealso}
%======================================================================
\section{PEP 305: Comma-separated Files \label{section-pep305}}
Comma-separated files are a format frequently used for exporting data
from databases and spreadsheets. Python 2.3 adds a parser for
comma-separated files.
The format is deceptively simple at first glance:
\begin{verbatim}
Costs,150,200,3.95
\end{verbatim}
Read a line and call \code{line.split(',')}: what could be simpler?
But toss in string data that can contain commas, and things get more
complicated:
\begin{verbatim}
"Costs",150,200,3.95,"Includes taxes, shipping, and sundry items"
\end{verbatim}
A big ugly regular expression can parse this, but using the new
\module{csv} package is much simpler:
\begin{verbatim}
from csv import csv
input = open('datafile', 'rb')
reader = csv.reader(input)
for line in reader:
print line
\end{verbatim}
The \function{reader} function takes a number of different options.
The field separator isn't limited to the comma and can be changed to
any character, and so can the quoting and line-ending characters.
Different dialects of comma-separated files can be defined and
registered; currently there are two, both for Microsoft Excel.
A separate \class{csv.writer} class will generate comma-separated files
from a succession of tuples or lists, quoting strings that contain the
delimiter.
\begin{seealso}
\seepep{305}{CSV File API}{Written and implemented
by Kevin Altis, Dave Cole, Andrew McNamara, Skip Montanaro, Cliff Wells.
}
\end{seealso}
%======================================================================
\section{Extended Slices\label{section-slices}}
......
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