an ugly file-reading pattern

[Skip Montanaro]

    Istvan> if I choose to process the file line by line the "Learning
    Istvan> Python" book advises me to use the following atrocity:

    Istvan> while 1:
    Istvan>     line = file.readline()
    Istvan>     if not line: break

    Istvan> Maybe I'm picky here but having to start an infinite loop then
    Istvan> needing a conditional to break out of it is anything but an
    Istvan> elegant pattern.

    Istvan> This has left me wondering about python,

Recent versions of Python (2.2 and later) allow this:

    file = file("somefile")
    for line in file:
        process(line)

It does the right thing from an efficiency standpoint, neither slurping the
file in all at once nor reading it line-by-line or char-by-char.

Note also that in 2.2 and later there is a file object in builtins ("open"
and "file" are the same object).  "open" is discouraged.  "file" is
preferred.

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