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mutable objects as default arguments

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rasbt 2014-04-15 18:08:23 -04:00
parent 7b07896b8e
commit 2e975a9c30
2 changed files with 8 additions and 4 deletions
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6
.ipynb_checkpoints/not_so_obvious_python_stuff-checkpoint.ipynb
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@ -1,7 +1,7 @@
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@ -200,7 +200,9 @@
"This oddity occurs, because Python tends to stores small integers as the same object, but not so for larger ones! \n",
"(*I received a comment that this is in fact a CPython artefact and must not necessarily be true in all implementations of Python!*)\n",
"\n",
"So the take home message is: always use \"==\" for equality, \"is\" for identity!"
"So the take home message is: always use \"==\" for equality, \"is\" for identity!\n",
"\n",
"Here is a [nice article](http://python.net/%7Egoodger/projects/pycon/2007/idiomatic/handout.html#other-languages-have-variables) explaining it using \"boxes\" (for people with C background) and \"name tags\" (in the case of Python):"
]
},
{

6
not_so_obvious_python_stuff.ipynb
View File

@ -1,7 +1,7 @@
{
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"name": "",
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@ -200,7 +200,9 @@
"This oddity occurs, because Python tends to stores small integers as the same object, but not so for larger ones! \n",
"(*I received a comment that this is in fact a CPython artefact and must not necessarily be true in all implementations of Python!*)\n",
"\n",
"So the take home message is: always use \"==\" for equality, \"is\" for identity!"
"So the take home message is: always use \"==\" for equality, \"is\" for identity!\n",
"\n",
"Here is a [nice article](http://python.net/%7Egoodger/projects/pycon/2007/idiomatic/handout.html#other-languages-have-variables) explaining it using \"boxes\" (for people with C background) and \"name tags\" (in the case of Python):"
]
},
{