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How to append contents of multiple files into one file
... should be >> right ? and also why is there a newline before all the text in my 0.txt file ?
– Steam
Aug 2 '13 at 0:00
2
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How to list imported modules?
How to enumerate all imported modules?
9 Answers
9
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If table exists drop table then create it, if it does not exist just create it
...s case than not to cover, see locking note below).
Second RENAME ... atomically replaces table definition, refer to
MySQL manual
for details.
At last, DROP ... just cleans up the old table,
obviously.
Wrapping all statements with something like SELECT GET_LOCK('__upgrade', -1); ... DO RELEASE_LOCK...
Python: Bind an Unbound Method?
In Python, is there a way to bind an unbound method without calling it?
5 Answers
5
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How to check that an element is in a std::set?
... Note that using count() instead of find() is never better but potentially worse. This is because find() will return after the first match, count() will always iterate over all elements.
– Frerich Raabe
Nov 9 '09 at 15:50
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How to measure time in milliseconds using ANSI C?
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Doesn't this measure cpu time and not wall time?
– krs013
Feb 1 '15 at 4:53
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show 1 more comment
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Leaflet - How to find existing markers, and delete markers?
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Should be a way to collect all of the layers used by Leaflet. :/
– jackyalcine
Aug 1 '12 at 21:39
10
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Why dict.get(key) instead of dict[key]?
...
It allows you to provide a default value if the key is missing:
dictionary.get("bogus", default_value)
returns default_value (whatever you choose it to be), whereas
dictionary["bogus"]
would raise a KeyError.
If omitted...
Access nested dictionary items via a list of keys?
...ist, value):
getFromDict(dataDict, mapList[:-1])[mapList[-1]] = value
All but the last element in mapList is needed to find the 'parent' dictionary to add the value to, then use the last element to set the value to the right key.
Demo:
>>> getFromDict(dataDict, ["a", "r"])
1
>>&g...
Preferred way to create a Scala list
...do so with a tail-recursive function, foldLeft, or something else is not really relevant.
If you get the elements in the same order you use them, then a ListBuffer is most likely a preferable choice, if performance is critical.
But, if you are not on a critical path and the input is low enough, yo...