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How does type Dynamic work and how to use it?

...g is that even the return type is correct - even though we had to add some casts. But Scala would not be Scala when there is no way to find a way around such flaws. In our case we can use type classes to avoid the casts: object DynTypes { sealed abstract class DynType[A] { def exec(as: A*): ...
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What does an exclamation mark mean in the Swift language?

...eLabel!.text Implicitly unwrapped optionals: var logo: UIImageView! Forced casting: logo.image = thing as! UIImage Unhandled exceptions: try! NSJSONSerialization.JSONObjectWithData(data, []) Every one of these is a different language construct with a different meaning, but they all have three impo...
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In Firebase, is there a way to get the number of children of a node without loading all the node dat

...riority(user,count); } </script> The 'risk' here is that a vote is cast, but the count not updated (haking or script failure). This is why the votes have a unique 'priority' - the script should really start by ensuring that there is no vote with priority higher than the current count, if the...
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print call stack in C or C++

...; int line = -1; char const* file; uintptr_t ip2 = reinterpret_cast<uintptr_t>(ip); Dwfl_Module* module = dwfl_addrmodule(dwfl, ip2); char const* name = dwfl_module_addrname(module, ip2); function = name ? demangle(name) : "<unknown>"; if (Dwfl_Line* dwfl_line...
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Add a new item to a dictionary in Python [duplicate]

... For Python 3, a quick fix to still use @Pakman comment is to cast the output of dict.items() in a list as follows: dict(list(default_data.items()) + list({'item3': 3}.items())), or even use the more idomatic: {**default_data, **{'item3': 3}} – H. Rev. ...
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Correct way to override Equals() and GetHashCode() [duplicate]

...s a RecommendationDTO. // The initial null check is unnecessary as the cast will result in null // if obj is null to start with. var recommendationDTO = obj as RecommendationDTO; if (recommendationDTO == null) { // If it is null then it is not equal to this instance. ...
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How to find the kth smallest element in the union of two sorted arrays?

...ithmic. (Here we are getting rid of half). In order to do that, we need to select one array whose one of the halves we can safely ignore. How do we do that? By confidently eliminating the half we know for sure is not going to have the kth element. – lambdapilgrim ...
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Is null reference possible?

...ingleton object that represents NULL within the class as follows and add a cast-to-pointer operator that returns nullptr ? Edit: Corrected several mistypes and added if-statement in main() to test for the cast-to-pointer operator actually working (which I forgot to.. my bad) - March 10 2015 - // E...
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Set value to NULL in MySQL

... ... assuming that you don't cast $mycolupdate to string at a later stage. – Álvaro González Oct 7 '13 at 16:27 add a comment ...
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How can I get a count of the total number of digits in a number?

...ointed out in the comment section, the LOG10 method had to be fixed with a casting to double inside Math.Abs() for the case when the input value is int.MinValue or long.MinValue. Regarding the early performance tests I've implemented before editing this question (it had to be edited a million times...