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Check if null Boolean is true results in exception
...r null as 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) { ... }
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How exactly does a generator comprehension work?
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Do you understand list comprehensions? If so, a generator expression is like a list comprehension, but instead of finding all the items you're interested and packing them into list, it waits, and yields each item out of the expression, one...
How do I initialize a TypeScript object with a JSON object
...hots at this to show a few different ways. They are by no means "complete" and as a disclaimer, I don't think it's a good idea to do it like this. Also the code isn't too clean since I just typed it together rather quickly.
Also as a note: Of course deserializable classes need to have default const...
How is null + true a string?
...where op is an overloadable binary operator, x is an expression of type X, and y is an expression of type Y, is processed as follows:
The set of candidate user-defined operators provided by X and Y for the operation operator op(x, y) is determined. The set consists of the union of the candid...
Check if a folder exist in a directory and create them using C#
How can I check if directory C:/ contains a folder named MP_Upload , and if it does not exist, create the folder automatically?
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How to query SOLR for empty fields?
I have a large solr index, and I have noticed some fields are not updated correctly (the index is dynamic).
7 Answers
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Cell spacing in UICollectionView
...in case anyone still needs correct answer here what you need:
Override standard flow layout.
Add implementation like that:
- (NSArray *) layoutAttributesForElementsInRect:(CGRect)rect {
NSArray *answer = [super layoutAttributesForElementsInRect:rect];
for(int i = 1; i < [answer count]...
PDO mysql: How to know if insert was successful
I'm using PDO to insert a record (mysql and php)
7 Answers
7
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What does the thread_local mean in C++11?
I am confused with the description of thread_local in C++11. My understanding is, each thread has unique copy of local variables in a function. The global/static variables can be accessed by all the threads (possibly synchronized access using locks). And the thread_local variables are visible to...
How to write a simple Html.DropDownListFor()?
...ic options. For example I'd like to provide choices between "Red", "Blue", and "Green".
7 Answers
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