scope hacks

[Andy Freeman]

I like local functions that can be recursive AND have access
to the enclosing function's state.  I tried to use locals()
in the following way and ran into a bug; is it me or Python 1.5?


With the tagged line, everything works as expected.  Without
the tagged line, inner's second print is {'j' : <value>};
it doesn't include inner's definition.  (It behaves like a
bogus optimization, namely, not adding local fns to the local
scope unless there's some "not call" reference or an explicit
locals(), the bogosity being that the default for v is an
explicit use of locals().)

def outer(j):
    def inner(i, v = locals()):    # v should get outer's locals()
        print "inner: " + str(i)
        print v
        if i:
            return i + v['inner'](i-1)
        else:
            return 1
    locals()             # why is this line necessary?

    print "outer"
    inner(j)

thanks,
-andy


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