On Wed, Feb 13, 2013 at 10:02 AM, Victor Stinner <victor.stin...@gmail.com> wrote: > I added a _PyUnicodeWriter internal API to optimize str%args and > str.format(args). It uses a buffer which is overallocated, so it's > basically like CPython str += str optimization. I still don't know how > efficient it is on Windows, since realloc() is slow on Windows (at > least on old Windows versions). > > We should add an official and public API to concatenate strings. I > know that PyPy has already its own API. Example: > > writer = UnicodeWriter() > for item in data: > writer += item # i guess that it's faster than writer.append(item) > return str(writer) # or writer.getvalue() ? > > I don't care of the exact implementation of UnicodeWriter, it just > have to be as fast or faster than ''.join(data). > > I don't remember if _PyUnicodeWriter is faster than StringIO or > slower. I created an issue for that: > http://bugs.python.org/issue15612 > > Victor
it's in __pypy__.builders (StringBuilder and UnicodeBuilder). The API does not really matter, as long as there is a way to preallocate certain size (which I don't think there is in StringIO for example). bytearray comes close but has a relatively inconvinient API and any pure-python bytearray wrapper will not be fast on CPython. _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
