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typeof !== “undefined” vs. != null
...gument, or as a global variable), I think the best way to do it is:
if (my_variable === undefined)
jQuery does it, so it's good enough for me :-)
Otherwise, you'll have to use typeof to avoid a ReferenceError.
If you expect undefined to be redefined, you could wrap your code like this:
(functi...
Proper use cases for Android UserManager.isUserAGoat()?
...changed in API 21.
/**
* Used to determine whether the user making this call is subject to
* teleportations.
* @return whether the user making this call is a goat
*/
public boolean isUserAGoat() {
return false;
}
It looks like the method has no real use for us as developers. Someone has ...
Path of assets in CSS files in Symfony 2
...ge in /web/bundles/mynicebundle/images/devil.png
I have made a test with ALL possible (sane) combinations of the following:
@notation, relative notation
Parse with cssrewrite, without it
CSS image background vs direct <img> tag src= to the very same image than CSS
CSS parsed with assetic a...
Obtain Bundle Identifier programmatically
...n approach to get the value. ARC example is following:
NSString *value = (__bridge_transfer NSString *)CFDictionaryGetValue(CFBundleGetInfoDictionary(CFBundleGetMainBundle()),
(const void *)(@"CFBundleIdentifier"));
...
Why does this async action hang?
I have a multi-tier .Net 4.5 application calling a method using C#'s new async and await keywords that just hangs and I can't see why.
...
How to delete a file or folder?
...mdir() removes an empty directory.
shutil.rmtree() deletes a directory and all its contents.
Path objects from the Python 3.4+ pathlib module also expose these instance methods:
pathlib.Path.unlink() removes a file or symbolic link.
pathlib.Path.rmdir() removes an empty directory.
...
Pandas: drop a level from a multi-level column index?
...
@yoonghm It is there, you are probably just calling it on columns that don't have a multi-index
– matt harrison
Dec 18 '18 at 14:59
1
...
How to free memory in Java?
...
Java uses managed memory, so the only way you can allocate memory is by using the new operator, and the only way you can deallocate memory is by relying on the garbage collector.
This memory management whitepaper (PDF) may help explain what's going on.
You can also call Sy...
Entity Framework: How to disable lazy loading for specific query?
...ed Aug 14 '15 at 14:13
William BallesterosWilliam Ballesteros
98188 silver badges88 bronze badges
...
SQL - Update multiple records in one query
...e updated so it's just u need to add the parent id and child ids to update all the rows u need using a small script.
UPDATE [Table]
SET couloumn1= (select couloumn1 FROM Table WHERE IDCouloumn = [PArent ID]),
couloumn2= (select couloumn2 FROM Table WHERE IDCouloumn = [PArent ID]),
co...