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Why do some claim that Java's implementation of generics is bad?
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Sorry, why is the last line a compile error? I'm messing around with it in Eclipse & can't get it to fail there - if I add enough stuff for the rest of it to compile.
– oconnor0
Feb 4 '10 at 21:44
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Nested defaultdict of defaultdict
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For an arbitrary number of levels:
def rec_dd():
return defaultdict(rec_dd)
>>> x = rec_dd()
>>> x['a']['b']['c']['d']
defaultdict(<function rec_dd at 0x7f0dcef81500>, {})
>>> print json.dumps(x)
{"a": {"b": {"c": {"d": {}}}}}
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Remove multiple whitespaces
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// string(11) "this works."
I'm not sure if it was just a transcription error or not, but in your example, you're using a single-quoted string. \n and \t are only treated as new-line and tab if you've got a double quoted string. That is:
'\n\t' != "\n\t"
Edit: as Codaddict pointed out, \s\s+ w...
How to shuffle a std::vector?
...#include <algorithm>
#include <random>
auto rng = std::default_random_engine {};
std::shuffle(std::begin(cards_), std::end(cards_), rng);
Live example on Coliru
Make sure to reuse the same instance of rng throughout multiple calls to std::shuffle if you intend to generate different p...
Linux command or script counting duplicated lines in a text file?
...3
}
or you can use a simple one-liner:
$ cat filename | python3 -c 'print(__import__("json").dumps(__import__("collections").Counter(map(str.strip, __import__("fileinput").input())), indent=2))'
share
|
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How do I make JavaScript beep?
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I get TypeError: sound.Play is not a function (in Firefox).
– ashleedawg
Feb 18 '19 at 12:51
3
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php $_POST array empty upon form submission
...ed to share it as it cost me much time.
When using JSON content-type the $_POST array will not populate (only with multi-part forms I believe)
Here is what did work to correct the issue:
$rest_json = file_get_contents("php://input");
$_POST = json_decode($rest_json, true);
hope this helps someo...
Updating MySQL primary key
I have a table user_interactions with 4 columns:
3 Answers
3
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Find all files with name containing string
... find . -name "*string*" Works great too. Removing . throws an error on my end. Thanks again @Zagorax.
– Dru
Jul 4 '12 at 13:49
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std::mutex 加锁抛 _DEVICE_OR_RESOURCE_BUSY 异常 - C/C++ - 清泛网 - 专注C/C++及内核技术
std::mutex 加锁抛 _DEVICE_OR_RESOURCE_BUSY 异常device_or_resource_busy最近遇到一个崩溃，在 std::lock_guard<std::mutex> lock(mutex_); 的地方，抛出了_DEVICE_OR_RESOURCE_BUSY 的异常。最终查出原因是：同一个线程对同一个mutex二次加锁导致的 最近遇到...