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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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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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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...
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...
What's the difference between event.stopPropagation and event.preventDefault?
...;/div>
With stopPropagation, only the button's click handler is called while the div's click handler never fires.
Where as if you use preventDefault, only the browser's default action is stopped but the div's click handler still fires.
Below are some docs on the DOM event properties and ...
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...