tree cc1b305ac162b2853faff244f550add4677b8d87
parent 1a0b87266540c6da06d3dd62248b1a4be660631a
author Guido van Rossum <guido@python.org> 902511909 +0000
committer Guido van Rossum <guido@python.org> 902511909 +0000
HG:extra convert_revision:svn%3A6015fed2-1504-0410-9fe1-9d1591cc4771/python/branches/legacy-trunk%4011360

Add warning that mutable argument defaults are evaluated only once;
with examples and workaround.  This keeps coming up, and I believe
that this section in the tutorial may have been (in part) the source
of the confusion.  While it didn't show examples with [] for a default,
it also didn't emphasize enough why that would be a bad idea, and
while it did say that defaults are evaluated at the point of function
definition, the example was not relevant for this issue.