Lazy file.readlines()?

[Marc Christiansen]

Neil Schemenauer <nascheme at ucalgary.ca> wrote:
> What would be cool is if readlines() returned a lazy sequence
> object (ie. only read as much is needed using a certain block
> size).  This should give the advantages of readlines() without
> the concern about sucking up a huge file all at once.
> 
> I implemented this idea (probably badly) in pure Python
> and got about a 2x speedup verses readline().  It is a small
> module so I will post it here.

Here it's the other way round:

14.SRam:> python BlockFile.py daten:programme/python/e4xtc.txt
block time 9.74225389957
normal time 5.96557199955

This is on an Amiga, using Python 1.5.2, the file is 276089 Bytes long.
I tried also with blocksizes of 100k and 8k for BlockFile, but the
difference was about nought, so the speed difference is not blocksize
related.

And there is a error in _get_block(self):

>         self.lines[0] = self.lines[0] + self.end

This should read: self.lines[0] = self.end + self.lines[0]

Ciao
  Marc
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