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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. ...
JavaScript OOP in NodeJS: how?
...onstructor.apply( this, arguments );
}
//Pointless override to show super calls
//note that for performance (e.g. inlining the below is impossible)
//you should do
//method.$getAge = _super.getAge;
//and then use this.$getAge() instead of super()
method.getAge = function() {
return _super.getAge...
Use find command but exclude files in two directories
...k for files with the name ending in _peaks.bed
! -path "./tmp/*" - Exclude all results whose path starts with ./tmp/
! -path "./scripts/*" - Also exclude all results whose path starts with ./scripts/
Testing the Solution:
$ mkdir a b c d e
$ touch a/1 b/2 c/3 d/4 e/5 e/a e/b
$ find . -type f ! -p...
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 use if/else in a dictionary comprehension?
...
@Marcin's answer covers it all, but just in case someone wants to see an actual example, I add two below:
Let's say you have the following dictionary of sets
d = {'key1': {'a', 'b', 'c'}, 'key2': {'foo', 'bar'}, 'key3': {'so', 'sad'}}
and you want ...
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 to properly overload the
I am writing a small matrix library in C++ for matrix operations. However my compiler complains, where before it did not. This code was left on a shelf for 6 months and in between I upgraded my computer from debian etch to lenny (g++ (Debian 4.3.2-1.1) 4.3.2
) however I have the same problem on a Ub...