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What exactly does += do in python?
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In Python, += is sugar coating for the __iadd__ special method, or __add__ or __radd__ if __iadd__ isn't present. The __iadd__ method of a class can do anything it wants. The list object implements it and uses it to iterate over an iterable object appending each...
Targeting only Firefox with CSS
...more on "using selector hacks" and on how the example you provided specifically works? Thanks.
– jj_
Nov 30 '14 at 11:15
1
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What is a good Hash Function?
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For doing "normal" hash table lookups on basically any kind of data - this one by Paul Hsieh is the best I've ever used.
http://www.azillionmonkeys.com/qed/hash.html
If you care about cryptographically secure or anything else more advanced, then YMMV. If you just want...
Use gulp to select and move directories and their files
I'm currently using gulp to call a bash script that cleans my dist/ directory and moves the appropriate files to the clean directory. I would like this to be done with gulp because I am not sure the script would work on a non *nix file system.
So far, I'm using the gulp-clean module to clean the...
Rename specific column(s) in pandas
I've got a dataframe called data . How would I rename the only one column header? For example gdp to log(gdp) ?
5 Answe...
【解决】scrapyd启动job时报错：exceptions.TypeError: __init__() got an ...
【解决】scrapyd启动job时报错：exceptions.TypeError: __init__() got an unexpected keyword argument '_job'进入项目spiders目录, 修改 spider py 文件（你自己的spider的主文件）：def __init__(self):改为：def __init__(self, *args, **kwargs):最后不要忘了重新部署一...
Are nested try/except blocks in python a good programming practice?
...EAFP.
Personally, I prefer to avoid nesting when it's not necessary:
def __getattribute__(self, item):
try:
return object.__getattribute__(item)
except AttributeError:
pass # fallback to dict
try:
return self.dict[item]
except KeyError:
raise Attrib...
Requirejs domReady plugin vs Jquery $(document).ready()?
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It seems like all the key points were already hit, but a few details fell through the cracks. Mainly:
domReady
It is both a plugin and a module. If you include it in the the requirements array w/ a trailing ! your module won't execute un...
Why does ++[[]][+[]]+[+[]] return the string “10”?
...array ([]). Due to references it's wrong to say [[]][0] === [], but let's call the inner array A to avoid the wrong notation.
++ before its operand means “increment by one and return the incremented result”. So ++[[]][0] is equivalent to Number(A) + 1 (or +A + 1).
Again, we can simplify the me...
浅析为什么char类型的范围是 -128~+127 - C/C++ - 清泛网 - 专注C/C++及内核技术
...减法，它会转化为1+(-1) ,因此
0000 0001
+ 1000 0001
____________________
1000 0010 …………… -2 ，1-1= -2? 这显然是不对了，所以为了避免减法运算错误，计算机大神们发明出了反码，直接用最高位表示符号位的叫做...