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How should one use std::optional?

...std::string s, int& i); Another way that this could be done is especially bad: int* try_parse_int(std::string s); //return nullptr if fail This requires dynamic memory allocation, worrying about ownership, etc. - always prefer one of the other two signatures above. Another example: clas...
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How do I encode and decode a base64 string?

..., I'll agree that wrapping a deref error is definitely dubious (plus we're all slowly agreeing to the fact that null as a concept is a bit of a hack to begin with), but we can still see some effects otherwise: the parameter name given in the exception might not be correct if left unchecked. ...
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What does “WARN Could not determine content-length of response body.” mean and how to I get rid of i

...e to a future release of Ruby. I'm using rails 3.2.0 on ruby 1.9.3-p0 installed through RVM as a single user. So the location in my case is: ~/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/1.9.1/webrick/httpresponse.rb The location of the file to be altered differs depending on the type of installation, R...
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How to convert an entire MySQL database characterset and collation to UTF-8?

... @Andrew Large production systems usually have a mirrored DB for maintenance. – BalusC Nov 30 '17 at 16:19 1 ...
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Calculating distance between two points, using latitude longitude?

...Java code given by Dommer above gives slightly incorrect results but the small errors add up if you are processing say a GPS track. Here is an implementation of the Haversine method in Java which also takes into account height differences between two points. /** * Calculate distance between two po...
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Static methods - How to call a method from another method?

... class.method should work. class SomeClass: @classmethod def some_class_method(cls): pass @staticmethod def some_static_method(): pass SomeClass.some_class_method() SomeClass.some_static_method() sha...
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What do the plus and minus signs mean in Objective-C next to a method?

... code. @interface NSArray : NSObject { } + (NSArray *)array; - (id)objectAtIndex:(NSUInteger)index; @end // somewhere else: id myArray = [NSArray array]; // see how the message is sent to NSArray? id obj = [myArray objectAtIndex:4]; // here the message is sent to myArray // Btw, in prod...
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What's the difference between == and .equals in Scala?

...ml#isNaN(double) Scala: http://www.scala-lang.org/files/archive/api/2.11.8/index.html#scala.Double@isNaN():Boolean share | improve this answer | follow | ...
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What is the difference (if any) between Html.Partial(view, model) and Html.RenderPartial(view,model)

... The usage of the two methods is slightly different: @Html.Partial("_yourPartialView") @{ Html.RenderPartial("_yourPartialView "); } The choice of which to use depends on your requirements. If you need to further manipulate the string being injected in the response stream, you shoul...
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Rails 3.1: Engine vs. Mountable App

...s, someone please let me know and I'll fix this response. I have made a small article about the subject here Cheers! share | improve this answer | follow | ...