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function runs. Import statements have a cost, so try to make sure
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they don't run inside hot functions.
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* Please write PEP-8__ compliant code.
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* Please write PEP-8__ compliant code.
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One often-missed requirement is that the first line of docstrings
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should be a self-contained one-sentence summary.
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__ http://www.python.org/peps/pep-0008.html
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mentioned, but new commands, changes in behaviour or fixed nontrivial
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45
bugs should be listed. See the existing entries for an idea of what
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(The strategy described here is what we want to get to, but it's not
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consistently followed in the code at the moment.)
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bzrlib is intended to be a generically reusable library. It shouldn't
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write messages to stdout or stderr, because some programs that use it
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might want to display that information through a GUI or some other
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We can distinguish two types of output from the library:
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1. Structured data representing the progress or result of an
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operation. For example, for a commit command this will be a list
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of the modified files and the finally committed revision number
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These should be exposed either through the return code or by calls
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to a callback parameter.
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A special case of this is progress indicators for long-lived
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operations, where the caller should pass a ProgressBar object.
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2. Unstructured log/debug messages, mostly for the benefit of the
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developers or users trying to debug problems. This should always
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be sent through ``bzrlib.trace`` and Python ``logging``, so that
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it can be redirected by the client.
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The distinction between the two is a bit subjective, but in general if
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there is any chance that a library would want to see something as
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structured data, we should make it so.
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The policy about how output is presented in the text-mode client
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should be only in the command-line tool.