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isset() and empty() - what to use
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It depends what you are looking for, if you are just looking to see if it is empty just use empty as it checks whether it is set as well, if you want to know whether something is set or not use isset.
Empty checks if the var...
PHP & mySQL: Year 2038 Bug: What is it? How to solve it?
...g of using TIMESTAMP to store the date+time, but I read that there is a limitation of year 2038 on it. Instead of asking my question in bulk, I preferred to break it up into small parts so that it is easy for novice users to understand as well. So my question(s):
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Objective-C declared @property attributes (nonatomic, copy, strong, weak)
...so atomic variables are threadsafe (can be accessed from multiple threads without botching of data)
Copy
copy is required when the object is mutable. Use this if you need the value of the object as it is at this moment, and you don't want that value to reflect any changes made by other owners of the...
What is the usefulness of `enable_shared_from_this`?
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It enables you to get a valid shared_ptr instance to this, when all you have is this. Without it, you would have no way of getting a shared_ptr to this, unless you already had one as a member. This example from the boost docu...
Where am I wrong about my project and these Javascript Frameworks?
...ge web app. I plan on having a set of features available from the get-go with plenty of feature additions down the road.
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Virtual Memory Usage from Java under Linux, too much memory used
I have a problem with a Java application running under Linux.
8 Answers
8
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C++ Object Instantiation
...n your user code.
As you say, when the variable is declared on the stack, its destructor is automatically called when it goes out of scope, which is your main tool for tracking resource lifetime and avoiding leaks.
So in general, every time you need to allocate a resource, whether it's memory (by ...
How to find if a given key exists in a C++ std::map
I'm trying to check if a given key is in a map and somewhat can't do it:
14 Answers
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What is JNDI? What is its basic use? When is it used?
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What is JNDI ?
It stands for Java Naming and Directory Interface.
What is its basic use?
JNDI allows distributed applications to look up services in an abstract, resource-independent way.
When it is used?
The most common use ca...
Python: split a list based on a condition?
...the best way, both aesthetically and from a performance perspective, to split a list of items into multiple lists based on a conditional? The equivalent of:
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