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How to read environment variables in Scala
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Now that I use Scala on a daily basis, I must move the accepted answer to @paradigmatic's answer. It uses Scala API and if used as suggested in the comments can return an Option.
– summerbulb
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Is “else if” a single keyword?
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They are not a single keyword if we go to the draft C++ standard section 2.12 Keywords table 4 lists both if and else separately and there is no else if keyword. We can find a more accessible list of C++ keywords by going to cppreferences section on keyw...
How to get line count of a large file cheaply in Python?
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num_lines = sum(1 for line in open('myfile.txt') if line.rstrip()) for filter empty lines
– Honghe.Wu
Mar 3 '14 at 9:26
62
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How to encrypt/decrypt data in php?
...= openssl_random_pseudo_bytes($key_size, $strong);
// $strong will be true if the key is crypto safe
This can be done once or multiple times (if you wish to create a chain of encryption keys). Keep these as private as possible.
IV
The initialisation vector adds randomness to the encryption and r...
Is there a pattern for initializing objects created via a DI container
...my objects and I want to have some initialization parameters that are not known until run-time:
5 Answers
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STL：accumulate与自定义数据类型 - C/C++ - 清泛网 - 专注C/C++及内核技术
...mulate()的原型为(文件取自DEV-C++编译器)：
template<typename _InputIterator, typename _Tp, typename _BinaryOperation>
_Tp accumulate(_InputIterator __first, _InputIterator __last, _Tp __init,
_BinaryOperation __binary_op)
{
// concept requirements
__glibcxx...
How do I change selected value of select2 dropdown with JqGrid?
...irst I initialize select2 on my select:
$('#my-best-friend').select2();
Now I manually select Bob in the browser. Next Bob does something naughty and I don't like him anymore. So the system unselects Bob for me:
$('#my-best-friend').val('').trigger('change');
Or say I make the system select th...
How can jQuery deferred be used?
...he best use case I can think of is in caching AJAX responses. Here's a modified example from Rebecca Murphey's intro post on the topic:
var cache = {};
function getData( val ){
// return either the cached value or jqXHR object wrapped Promise
return $.when(
cache[ val ] ||
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Hidden Features of Java
...d it, never heard of it before.
ThreadLocals are typically not so widely known as a way to store per-thread state.
Since JDK 1.5 Java has had extremely well implemented and robust concurrency tools beyond just locks, they live in java.util.concurrent and a specifically interesting example is the j...
Any way to delete in vim without overwriting your last yank? [duplicate]
...in the registers:
"_dd
See also :help registers.
It's probably safest, if you want to paste something over and over again, to yank it into a "named" register.
"aY
Yanks a line into the a register. Paste it with "ap.
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