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How do you append an int to a string in C++? [duplicate]

...irectly to it, as in std::cout << text << i; The C++ way of converting all kinds of objects to strings is through string streams. If you don't have one handy, just create one. #include <sstream> std::ostringstream oss; oss << text << i; std::cout << oss.str()...
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Drop multiple tables in one shot in mysql

...sing the below For sql server - SELECT CONCAT(name,',') Table_Name FROM SYS.tables; For oralce - SELECT CONCAT(TABLE_NAME,',') FROM SYS.ALL_TABLES; Copy and paste the table names from the result set and paste it after the DROP command. ...
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A fast method to round a double to a 32-bit int explained

... For those who'd like to convert to int64_t you can do that by shifting the mantissa left and then right by 13 bits. This will clear the exponent and the two bits from the 'magic' number, but will keep and propagate the sign to the entire 64-bit sign...
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Python int to binary string?

Are there any canned Python methods to convert an Integer (or Long) into a binary string in Python? 35 Answers ...
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Convert base class to derived class [duplicate]

Is it possible in C# to explicitly convert a base class object to one of it's derived classes? Currently thinking I have to create a constructor for my derived classes that accept a base class object as a parameter and copy over the property values. I don't really like this idea, so I'd like to avoi...
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Why covariance and contravariance do not support value type

...ntational forms, "boxed" and "unboxed". The compiler has to insert code to convert from one form to the other, even though this is normally invisible at a source code level. In effect, only the "boxed" form is considered by the underlying system to be a subtype of object, but the compiler automatica...
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Why does Python use 'magic methods'?

...those operations that were generic for a group of types and which were intended to work even for objects that didn’t have methods at all (e.g. tuples). It is also convenient to have a function that can readily be applied to an amorphous collection of objects when you use the functi...
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The server principal is not able to access the database under the current security context in SQL Se

...ARE orphanuser_cur cursor for SELECT UserName = su.name FROM sysusers su JOIN sys.server_principals sp ON sp.name = su.name WHERE issqluser = 1 AND (su.sid IS NOT NULL AND su.sid <> 0x0) AND suser_sname(su.sid) is null ORDER BY su.name ...
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How to check if an object is nullable?

...se I got a boxed Nullable<T> but because I was writing a generic WPF converter base class and some properties are nullable, so I used Nullable.GetUnderlyingType to detect that case and Activator.CreateInstance to make a boxed nullable, (Convert.ChangeType doesn't handle nullables btw). ...
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Accessing members of items in a JSONArray with Java

... put("b", 400); }} ))); //Then: convert to List<JSONObject> List<JSONObject> jsonItems = IntStream.range(0, jsonArray.length()) .mapToObj(index -> (JSONObject) jsonArray.get(index)) .collect(Collectors.toList()); ...