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What makes Scala's operator overloading “good”, but C++'s “bad”?
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C++ inherits true blue operators from C. By that I mean that the "+" in 6 + 4 is very special. You can't, for instance, get a pointer to that + function.
Scala on the other hand doesn't have operators in that way. It just has great flexibility in definin...
How to specify the location with wget?
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From the manual page:
-P prefix
--directory-prefix=prefix
Set directory prefix to prefix. The directory prefix is the
directory where all other files and sub-directories will be
saved to, i....
Check status of one port on remote host [closed]
...known ip:
nmap -A 192.168.0.5/32 -p 23
For example, look for open ports from 20 to 30 on host.example.com:
nc -z host.example.com 20-30
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Debugging Package Manager Console Update-Database Seed Method
...Entity Framework database configuration class when I run Update-Database from the Package Manager Console but didn't know how to do it. I wanted to share the solution with others in case they have the same issue.
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Validate decimal numbers in JavaScript - IsNumeric()
...hand side is now numeric, type coercion is again used. Now that the input from both sides was coerced to the same type from the same original value, you would think they should always be the same (always true). However, there's a special rule that says NaN is never equal to NaN, and so a value that...
Is there any way to check if iOS app is in background?
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From the docs: UIApplicationStateInactive - The app is running in the foreground but is not receiving events. This might happen as a result of an interruption or because the app is transitioning to or from the background.
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Conditional import of modules in Python
...her the OS the user is on is Windows or Linux. I take the OS name as input from the user. Now, is it correct to do the following?
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Proper use of beginBackgroundTaskWithExpirationHandler
... if (completion) {
//run the completion block and remove it from the completion block dictionary
completion();
[self.dictTaskCompletionBlocks removeObjectForKey:[NSNumber numberWithUnsignedLong:_key]];
}
}
@synchronized(self.dictTaskIdentifie...
What's better at freeing memory with PHP: unset() or $var = null
...a. You might get memory freed / shrunk faster, but it may steal CPU cycles from the code that truly needs them sooner, resulting in a longer overall execution time.
(Since 2013, that unset man page don't include that section anymore)
Note that until php5.3, if you have two objects in circular refer...
How to declare and add items to an array in Python?
...se append
my_list.append(12)
To extend the list to include the elements from another list use extend
my_list.extend([1,2,3,4])
my_list
--> [12,1,2,3,4]
To remove an element from a list use remove
my_list.remove(2)
Dictionaries represent a collection of key/value pairs also known as an as...