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Why is null an object and what's the difference between null and undefined?
... I don't know.
In short; undefined is where no notion of the thing exists; it has no type, and it's never been referenced before in that scope; null is where the thing is known to exist, but it's not known what the value is.
One thing to remember is that null is not, conceptually, the same as false ...
C# “internal” access modifier when doing unit testing
I'm new to unit testing and I'm trying to figure out if I should start using more of internal access modifier. I know that if we use internal and set the assembly variable InternalsVisibleTo , we can test functions that we don't want to declare public from the testing project. This makes me thi...
Better way to check variable for null or empty string?
...
// Function for basic field validation (present and neither empty nor only white space
function IsNullOrEmptyString($str){
return (!isset($str) || trim($str) === '');
}
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Going from a framework to no-framework [closed]
...eveloping in PHP for about 8 years as a hobby. In 2009, I picked up codeigniter and since then I've not managed to get a single project developed.
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Is it possible to set a custom font for entire of application?
... certain font for my entire application. I have .ttf file for the same.
Is it possible to set this as default font, at application start up and then use it elsewhere in the application? When set, how do I use it in my layout XMLs?
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What makes Lisp macros so special?
.... Let's invoke our suspension of disbelief and pretend Lisp has a very limited loop macro that just does iteration and no easy way to do the equivalent of list comprehensions.
In Lisp you could write the following. I should note this contrived example is picked to be identical to the Python co...
How can I change the file type association of an existing file in WebStorm?
I accidentally created a file with no extension and I chose the wrong file type association. Text Document I think. I renamed it to have the .js extension which is what I wanted, but now it's stuck without any syntax highlighting. WebStorm doesn't treat it as a javascript file. I can't find anyw...
“No X11 DISPLAY variable” - what does it mean?
...h
setenv DISPLAY :0.0
before running your app.
Actually, I'm surprised it isn't set automatically. Are you trying to start this application from a non-graphic terminal? If not, have you modified the default .profile, .login, .bashrc or .cshrc?
Note that setting the DISPLAY to :0.0 pre-suppose...
Java and SQLite [closed]
...provides. What driver/connector library is out there to connect and use SQLite with Java.
10 Answers
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Is there a way to get the source code from an APK file?
...hs.
All I have is the APK file that is stored in my email from when I sent it to a friend.
26 Answers
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