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Downcasting shared_ptr to shared_ptr?
...n the base class. Implicit casting like this may become the source of bugs and errors.
-Update: If the type is not polymorphic, std::static_pointer_cast may be used.
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Using {} in a case statement. Why?
What is the point with using { and } in a case statement? Normally, no matter how many lines are there in a case statement, all of the lines are executed. Is this just a rule regarding older/newer compilers or there is something behind that?
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Why malloc+memset is slower than calloc?
...se it can skip memset() entirely. In other cases, calloc() can even cheat and not allocate any memory! However, malloc()+memset() will always do the full amount of work.
Understanding this requires a short tour of the memory system.
Quick tour of memory
There are four main parts here: your prog...
JavaScript function in href vs. onclick
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The typical path these days is to use a javascript library (eg. jquery) and create an event handler using that library. It would look something like:
$('a').click( function(e) {e.preventDefault(); /*your_code_here;*/ return false; } );
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Understanding checked vs unchecked exceptions in Java
...ethrow) should not be used at all. They were eliminated in C# for example, and most languages don't have them. So you can always throw a subclass of RuntimeException (unchecked exception)
However, I think checked exceptions are useful - they are used when you want to force the user of your API to t...
Where is nodejs log file?
...ode.js "app" is a separate entity. By default it will log errors to STDERR and output to STDOUT. You can change that when you run it from your shell to log to a file instead.
node my_app.js > my_app_log.log 2> my_app_err.log
Alternatively (recommended), you can add logging inside your appli...
Calc of max, or max of calc in CSS
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min(), max(), and clamp() are finally available!
Starting in Firefox 75, Chrome 79, and Safari 11.1 (except clamp).
min() and max() take any number of arguments.
clamp() has syntax clamp(MIN, VAL, MAX) and is equivalent to max(MIN, min(...
NSString property: copy or retain?
... behind its back, you should mark the properties representing them copy. (And if you write the setter yourself instead of using @synthesize you should remember to actually use copy instead of retain in it.)
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Express-js wildcard routing to cover everything under and including a path
...o me as well. Unfortunately: passing an array to app.VERB() is deprecated and will be removed in 4.0
– CodeWarrior
Jul 26 '13 at 16:36
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What is the reason for having '//' in Python? [duplicate]
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In Python 3, they made the / operator do a floating-point division, and added the // operator to do integer division (i.e. quotient without remainder); whereas in Python 2, the / operator was simply integer division, unless one of the operands was already a floating point number.
In Python 2...