Mercurial > hg > config
annotate python/example/mutable_defaults.py @ 727:03b66f90916f
works
author | Jeff Hammel <k0scist@gmail.com> |
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date | Tue, 02 Dec 2014 13:59:37 -0800 |
parents | d6f659169b49 |
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add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
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1 #!/usr/bin/env python |
70544c7406e2
add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
diff
changeset
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2 |
184 | 3 # see also: http://www.daniweb.com/software-development/python/threads/66697 |
4 | |
91
70544c7406e2
add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
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changeset
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5 class Foo(object): |
70544c7406e2
add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
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changeset
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6 def __init__(self, mutable=['default']): |
70544c7406e2
add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
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7 self.foo = mutable |
70544c7406e2
add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
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changeset
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8 self.foo.append(1) |
70544c7406e2
add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
diff
changeset
|
9 |
70544c7406e2
add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
diff
changeset
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10 if __name__ == '__main__': |
70544c7406e2
add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
diff
changeset
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11 bar = Foo() |
70544c7406e2
add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
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changeset
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12 print len(bar.foo) |
70544c7406e2
add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
diff
changeset
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13 fleem = Foo() |
70544c7406e2
add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
diff
changeset
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14 print len(fleem.foo) |
70544c7406e2
add illustration program for mutable arguments, since this comes up a bunch
Jeff Hammel <jhammel@mozilla.com>
parents:
diff
changeset
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15 assert len(fleem.foo) == 2, "Don't use default mutable arguments!" |