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Using boolean values in C
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@NoBody Using a smaller type can save on memory, but it might not make it any faster. Often, it's faster to use the processor's native word size instead of a smaller size as it could require the compiler to make bit shifts to align it properly...
jQuery: checking if the value of a field is null (empty)
...ype]').val().length != 0){}
If you want to check if the element exist at all, you should do that before calling val:
var $d = $('#person_data[document_type]');
if ($d.length != 0) {
if ($d.val().length != 0 ) {...}
}
s...
What is the difference between `after_create` and `after_save` and when to use which?
... readers should note that, according to the docs, ActiveRecord's update_all does not invoke any callbacks, including after_*
– user2426679
Jan 10 at 19:34
add a comment
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Easiest way to check for an index or a key in an array?
... associative array)
[ ${array[key]+abc} ] && echo "exists"
Basically what ${array[key]+abc} does is
if array[key] is set, return abc
if array[key] is not set, return nothing
References:
See Parameter Expansion in Bash manual and the little note
if the colon is omitted, the ope...
Gesture recognizer and button actions
...nizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
// Disallow recognition of tap gestures in the segmented control.
if ((touch.view == yourButton)) {//change it to your condition
return NO;
}
return YES;
}
hope it will help
Edit
As Daniel noted you must con...
Returning an array using C
... use pointers for arrays when you return them. Being a new programmer, I really do not understand this at all, even with the many forums I have looked through.
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Octave-Gnuplot-AquaTerm error: set terminal aqua enhanced title “Figure 1”…unknown terminal type"
I've installed Octave and gnuplot via Homebrew, and downloaded AquaTerm.dmg.
When I try to plot, I get the following message:
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How do you increase the max number of concurrent connections in Apache?
...ts 200
MinSpareThreads 25
MaxSpareThreads 75
ThreadsPerChild 25
First of all, whenever an apache is started, it will start 2 child processes which is determined by StartServers parameter. Then each process will start 25 threads determined by ThreadsPerChild parameter so this means 2 process can se...
SHFileOperation函数总结（文件夹的移动、复制、删除） - C/C++ - 清泛网 -...
...I SHFileOperation(LPSHFILEOPSTRUCT lpFileOp);
参数：
typedef struct _SHFILEOPSTRUCT
{
HWND hwnd; //父窗口句柄
UINT wFunc; //要执行的动作
LPCTSTR pFrom; //源文件路径，可以是多个文件
LPCTSTR ...
Join strings with a delimiter only if strings are not null or empty
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.filter(Boolean) (which is the same as .filter(x => x)) removes all "falsy" values (nulls, undefineds, empty strings etc). If your definition of "empty" is different, then you'll have to provide it, for example:
[...].filter(x => typeof x === 'string' && x.length > 0)
wi...