On Sep 4, 2:14 am, Stefan Behnel <[EMAIL PROTECTED]> wrote: > castironpi wrote: > > Any interest in pursuing/developing/working together on a mmaped-xml > > class? Faster, not readable in text editor. > > Any hints on what you are talking about? > > Stefan
Nice to hear from you. I assumed you were familiar with the problem; you're not. In an XML file, entries are stored in serial, sort of like this. AAA BBB CCC DDD Or more recognizably, <A><B><C>something</C><D>something</D></B></A> Point is, to change <C>something</C> to <C>something else</C>, you have to recopy everything after that. AAA BBB CCC DDD AAA BBBb CCC DDD requires 7 writes, 'b CCC DDD', not 1. I want to use a simple tree structure to store: 0 A-> None, 1 1 B-> None, 2 2 C-> 3, None 3 D-> None, None Each node maps to 'Next, Child', or more accurately, 'Next Sibling, First Child'. You get constant time updates to contents, and log-time searches. There was a similar problem today in: From: Gerhard Häring <[EMAIL PROTECTED]> Date: Thu, 04 Sep 2008 13:08:59 +0200 Subject: Re: cPickle The OP wanted to update the third element in a pickled tuple, but not the first two. I propose to write a tree structure to a memory-mapped file. A heavyweight string class, Rope, I wrote, exceeded native string speeds at a file size of two megs. You could use that, or store the tree directly. The obstacle is probably mmap 'alloc' and 'free' routines, which I posted on Google Code. -- http://mail.python.org/mailman/listinfo/python-list
