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Detecting an undefined object property
...is the special value `undefined`");
}
To check if an object does not actually have such a property, and will therefore return undefined by default when you try and access it:
if(!o.hasOwnProperty('myProperty')) {
alert("myProperty does not exist");
}
To check if the value associated with an i...
git --git-dir not working as expected
...
Thanks this worked! Agreed that this is confusing. Its called Keep It Simple Stupid. You can almost always allow flexibility while at the same time giving defaults that make the most sense VS having a command not work at all.
– Nay
Jan 18 '12...
conditional unique constraint
...
That's only partially true onedaywhen. The database behaves consistently and predictably. The check constraint will execute after the row is added to the table and before the transaction is committed by the dbms and you can count on that. ...
Injecting $scope into an angular service function()
...table stuff), but is a Scope object. Many scope objects can be created (usually prototypically inheriting from a parent scope). The root of all scopes is the $rootScope and you can create a new child-scope using the $new() method of any scope (including the $rootScope).
The purpose of a Scope is t...
iOS 8 removed “minimal-ui” viewport property, are there other “soft fullscreen” solutions?
...ents of the main element). Disabling document scrolling
prevents accidentally leaving the minimal-ui when scrolling upwards.
As per the original iOS 7.1 spec, tapping the top bar brings back the
rest of the chrome.
The end result looks like this:
For the sake of documentation, and in case...
How can I get the current date and time in UTC or GMT in Java?
...TC. It's most accurate to say that Date itself doesn't have a time zone at all - it's just an instant in time, which could be regarded in multiple time zones. But when you create an instance, it doesn't depend on your time zone.
– Jon Skeet
Dec 28 '12 at 12:33
...
How can I tell if a DOM element is visible in the current viewport?
...ut the browser vendors have also created getBoundingClientRect for specifically the purpose of finding element coordinates... Why wouldn't we use it?
– Prestaul
Jul 6 '15 at 15:25
...
Android REST client, Sample?
...y if your use case demands it. For example, I do not have local storage at all; because my app can tolerate loss of a few REST responses.
My approach uses just AsyncTasks under the covers. In my case, I "call" these Tasks from my Activity instance; but to fully account for cases like screen rotation...
bool operator ++ and --
... and 2 or more [true]).
So as a short-hand ++ worked, and -- didn't.
++ is allowed on bools for compatibility with this, but its use is deprecated in the standard and it was removed in C++17.
This assumes that I only use x as an boolean, meaning that overflow can't happen until I've done ++ often e...
how to provide a swap function for my class?
...found through ADL
// some code ...
swap(lhs, rhs); // unqualified call, uses ADL and finds a fitting 'swap'
// or falls back on 'std::swap'
// more code ...
}
Is the proper way to provide a swap function for your class.
namespace Foo {
class Bar{}; // dummy
void ...