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Check if null Boolean is true results in exception
...s any other object.
In your particular case, your Boolean is null and the if statement triggers an implicit conversion to boolean that produces the NullPointerException. You may need instead:
if(bool != null && bool) { ... }
...
Unnamed/anonymous namespaces vs. static functions
...nly. The static keyword applied to entity declared in namespace scope specifies its internal linkage. Entity declared in anonymous namespace has external linkage (C++/3.5) however it is guaranteed to live in uniquely named scope. This anonymity of unnamed namespace effectively hides its declaratio...
AngularJS - how to get an ngRepeat filtered result reference
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The problem with this approach is that if you watch the assigned property, you'll end up spamming $digests (one per iteration)... Maybe there's some way to avoid this?
– Juho Vepsäläinen
Dec 24 '13 at 12:17
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How to check if an activity is the last one in the activity stack for an application?
I want to know if user would return to the home screen if he exit the current activity.
10 Answers
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What is the difference between . (dot) and $ (dollar sign)?
What is the difference between the dot (.) and the dollar sign ($) ?
13 Answers
13
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How can I use an array of function pointers?
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@crucifiedsoul "the C Programming Language" written by Brian Kernighan and Dennis Ritchie? It could be, but I didn't have it as a reference at the time I wrote the answer three and an half year ago. So I don't know.
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Remove duplicates in the list using linq
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Hi Christian , What will be the change in code if i have a List<my_Custom_Class> and List<string>. My custom class has various items in which one is DCN number and list<string> has only DCN number. So I need to check the List<Custom_Class> contains...
How to use a RELATIVE path with AuthUserFile in htaccess?
...lative paths for AuthUserFile:
File-path is the path to the user file. If it is not absolute (i.e., if it doesn't begin with a slash), it is treated as relative to the ServerRoot.
You have to accept and work around that limitation.
We're using IfDefine together with an apache2 command line ...
Storing Python dictionaries
... It's worth knowing about the third argument to pickle.dump, too. If the file doesn't need to be human-readable then it can speed things up a lot.
– Steve Jessop
Aug 18 '11 at 0:11
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Check whether or not the current thread is the main thread
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If you want a method to be executed on the main thread, you can:
- (void)someMethod
{
dispatch_block_t block = ^{
// Code for the method goes here
};
if ([NSThread isMainThread])
{
block();
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