Safe Psyco

[David Mertz, Ph.D.]

I wrote recently:
|Nonetheless, my article on Psyco recently appeared at:
|    http://www-106.ibm.com/developerworks/linux/library/l-psyco.html
|...It makes me wonder if Python programmers shouldn't start trying to
|import Psyco fairly routinely (in try/except blocks that fail gracefully
|where Psyco is absent).

I mentioned routine use of Psyco in this note earlier today.  I figured
I'd followup with more explicit description of what I mean.  You could
stick the following at the top of your script:

    try:
        import psyco
        from psyco.classes import *
    except ImportError:
        class _psyco:
            def jit(self):      pass
            def bind(self, f):  pass
            def proxy(self, f): return f
        psyco = _psyco()

This will be happy whether or not Psyco is installed on a given system.
Once this bit is at the top, you are free to scatter 'psyco.bind(func)',
'newfun = psyco.proxy(func)' and 'psyco.jit()' calls through the rest of
your script.  Obviously, which calls you decide to use is still
determined by the same principles as in a regular Psyco program.

But the nice thing about this block is that nothing at all bad will
happen if a user doesn't have Psyco.  All the calls will be dummies, and
no speedup will occur.  But the program will still run in a
non-specializing way... as plain Python.

Yours, David...

--
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