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Why are Perl 5's function prototypes bad?
...nd to expect prototypes to provide a mechanism for checking that function calls are correct: that is, that they have the right number and type of arguments. Perl's prototypes are not well-suited for this task. It's the misuse that's bad. Perl's prototypes have a singular and very different purpose:
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Using boolean values in C
...
@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...
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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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...
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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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 ...
In c++ what does a tilde “~” before a function name signify?
... memory, etc. etc.
Here's a description from ibm.com:
Destructors are usually used to deallocate memory and do other cleanup for a class object and its class members when the object is destroyed. A destructor is called for a class object when that object passes out of scope or is explicitly delete...
Percentage Height HTML 5/CSS
...’, which is the nearest ancestor to also be positioned.)
Alternatively, all modern browsers and IE>=9 support new CSS units relative to viewport height (vh) and viewport width (vw):
div {
height:100vh;
}
See here for more info.
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