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Why does the MongoDB Java driver use a random number generator in a conditional?

...k && Math.random() <= 0.1) return res; The commit that originally introduced this logic had if (_ok == true) { _logger.log( Level.WARNING , "Server seen down: " + _addr, e ); } else if (Math.random() < 0.1) { _logger.log( Level.WARNING , "Server seen down: " + _addr ); } —a...
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When is “i += x” different from “i = i + x” in Python?

... This depends entirely on the object i. += calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2. From an API perspective, __iadd__ is supposed to be used fo...
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What are Flask Blueprints, exactly?

...he string mold in Blueprint("mold", __name__) – Codevalley Aug 7 '17 at 6:48 8 ...
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Why can't I define a default constructor for a struct in .NET?

...type a default constructor is created (by the compiler?) which initialized all members to zero (or null ). 10 Answers ...
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Error handling in C code

... your library as painless as possible think about these additions: store all possible error-states in one typedef'ed enum and use it in your lib. Don't just return ints or even worse, mix ints or different enumerations with return-codes. provide a function that converts errors into something huma...
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mysql_fetch_array()/mysql_fetch_assoc()/mysql_fetch_row()/mysql_num_rows etc… expects parameter 1 to

... advice about how to properly catch errors in future, it should (IMHO) actually answer the specific question (ie explain why there's an error in this case). – Sepster Apr 23 '13 at 22:17 ...
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How do I check if a string is valid JSON in Python?

...SON. In general, the "Pythonic" philosophy for this kind of situation is called EAFP, for Easier to Ask for Forgiveness than Permission. share | improve this answer | follow...
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Execute code when Django starts ONCE only?

... entirely a separate problem. The idea of special one-time startup before all management commands is hard to understand. You'll have to provide something specific. Perhaps in another question. – S.Lott Feb 13 '12 at 12:49 ...
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Add a column with a default value to an existing table in SQL Server

...ed for Existing Records. If your Column is NOT NULL, then it will automatically use the Default Value     for all Existing Records, whether you specify WITH VALUES or not. How Inserts work with a Default-Constraint: If you insert a Record into SomeTable and do not Specify SomeCol's value, then it...
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ios Upload Image and Text using HTTP POST

...programmed to accept. NSMutableDictionary* _params = [[NSMutableDictionary alloc] init]; [_params setObject:[NSString stringWithString:@"1.0"] forKey:[NSString stringWithString:@"ver"]]; [_params setObject:[NSString stringWithString:@"en"] forKey:[NSString stringWithString:@"lan"]]; [_params setObje...