[Python-Dev] Re: Optional separatorargument for file.writelines()and StringIO.writelines() (original) (raw)

Raymond Hettinger python at rcn.com
Thu Feb 26 20:13:16 EST 2004

This is a big YES!

Actually, it's a big no. Alex, immediately and correctly pointed out that what is needed in a suffix rather than a separator and the way to get that is with a generator expression: f.writelines(x+'\n' for x in mylines).

I had been led astray because I was experimenting with using cStringIO.writelines() as a basis for implementing str.join() for general iterables without creating an intermediate tuple. Right now, ''.join(it) will unexpectedly consume much more memory than really needed.

Raymond Hettinger

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