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In Python, what is the difference between “.append()” and “+= []”?
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In general case append will add one item to the list, while += will copy all elements of right-hand-side list into the left-hand-side list.
Update: perf analysis
Comparing bytecodes we can assume that append version wastes cycles in LOAD_ATTR + CALL_FUNCTION, and += version -- in BUILD_LIST. App...
How can I use map and receive an index as well in Scala?
...t as you would do in Java. But it's not functional style. Think if you actually need it.
– Cristian Vrabie
Mar 12 '12 at 10:52
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Injecting content into specific sections from a partial view ASP.NET MVC 3 with Razor View Engine
...ours. In my answer I've expressed mine and linked to an answer which would allow you to achieve this task. But I've also highlighted on what I would recommend and do for this situation.
– Darin Dimitrov
Dec 7 '12 at 16:41
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Javascript - removing undefined fields from an object [duplicate]
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You actually don't even need the ternary operator. Instead you can do (obj[key]===undefined&& delete obj[key]) The reason this works is because and uses short-circuit evaluation, so once the first check fails the second isn'...
warning: implicit declaration of function
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@Flimm, C99 and C89/C90 has different setting for this
– How Chen
Jan 15 '15 at 6:06
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Keyboard shortcuts in WPF
I know about using _ instead of & , but I'm looking at all the Ctrl + type shortcuts.
10 Answers
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What is INSTALL_PARSE_FAILED_NO_CERTIFICATES error?
I was trying to change my default/main/startup (whatever you call it) activity by editing the androidmanifest.xml file. All i did was change the android:name property. however, this completely broke the entire app. when I try to install it fails and reads.
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Days between two dates? [duplicate]
...u’ve literally got two date objects, you can subtract one from the other and query the resulting timedelta object for the number of days:
>>> from datetime import date
>>> a = date(2011,11,24)
>>> b = date(2011,11,17)
>>> a-b
datetime.timedelta(7)
>>> ...
Functional programming - is immutability expensive? [closed]
...’d like to clarify some points.
The “in-place” quicksort isn’t really in-place (and quicksort is not by definition in-place). It requires additional storage in the form of stack space for the recursive step, which is in the order of O(log n) in the best case, but O(n) in the worst case.
Im...
How can I find the number of arguments of a Python function?
...ms = sig.parameters
print(params['kwarg1']) # prints: kwarg1=20
Additionally, you can call len on sig.parameters to also see the number of arguments this function requires:
print(len(params)) # 3
Each entry in the params mapping is actually a Parameter object that has further attributes makin...