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Why does ++[[]][+[]]+[+[]] return the string “10”?
... itself.
In this case, + sees two operands: a number and an array. It’s now trying to coerce the two into the same type. First, the array is coerced into the string "0", next, the number is coerced into a string ("1"). Number + String === String.
"1" + "0" === "10" // Yay!
Specification deta...
Can a shell script set environment variables of the calling shell? [duplicate]
...t is "setit" then do:
ln -s setit setit-sh
and
ln -s setit setit-csh
Now either directly or in an alias, you do this from sh
eval `setit-sh`
or this from csh
eval `setit-csh`
setit uses $0 to determine its output style.
This is reminescent of how people use to get the TERM environment v...
TypeScript static classes
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I have an use-case for having static classes. Right now, I have a class that only contains static methods. In the project we need to provide some sort of configuration for each class that can be instantiated. Declaring such class as static would not only help me notice that it...
Expand/collapse section in UITableView in iOS
... headers that are already there will be a pain. Based on the way they work now, I am not sure you can easily get actions out of them. You could set up a cell to LOOK like a header, and setup the tableView:didSelectRowAtIndexPath to manually expand or collapse the section it is in.
I'd store an arra...
push multiple elements to array
...s not work to add the 2nd array to the first. It will create a new one. I know it is similar. The spread operator is what I was looking for. Just look at the other answers and comments there for details.
– BluE
Feb 27 at 7:55
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Retrieving the last record in each group - MySQL
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MySQL 8.0 now supports windowing functions, like almost all popular SQL implementations. With this standard syntax, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY nam...
How to use '-prune' option of 'find' in sh?
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+1 finally found out why I need -print at end, I can now stop adding \! -path <pattern> in addition to -prune
– Miserable Variable
May 14 '13 at 20:39
6...
jQuery Ajax POST example with PHP
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Yes, I understand that now. But I found many examples that always put a $(document).ready block around so that the example is self-contained. I wrote the comment for a future user who may, like me, stumble on this and end-up reading the comment thr...
How to tell if UIViewController's view is visible
I have a tab bar application, with many views. Is there a way to know if a particular UIViewController is currently visible from within the UIViewController ? (looking for a property)
...
Connecting overloaded signals and slots in Qt 5
...amp;QSpinBox::valueChanged),
slider, &QSlider::setValue);
I know, it's ugly. But there's no way around this. Today's lesson is: do not overload your signals and slots!
Addendum: what's really annoying about the cast is that
one repeats the class name twice
one has to specify the ...