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Im having issues with adding a show instance to my data structure, wich is: data Structure = Structure String [Structure] and I would like to have this output: strct strct1 strct2 strct3 I've been trying this instance Show Structure where show (Structure a (xs)) = show a ++ "\n" ++ " " ++ show xs But its output is "strct" ["strct1" [], "strct2" []] So, I would need no brackets, no commas and no quotation marks. Any ideas? Thanks I'm sure there are better library routines for this, but wouldn't this work? unlines $ a : [" " ++ show x | x <- xs] However, that covers only one level. You probably

There is an Crypto.Random API inside the crypto-api package that specifies what it means for something to be a "pseudorandom number generator". I have implemented this API using an instance of System.Random's RandomGen class, namely, StdGen: instance CryptoRandomGen StdGen where newGen bs = Right $ mkStdGen $ shift e1 24 + shift e2 16 + shift e3 8 + e4 where (e1 : e2 : e3 : e4 : _) = Prelude.map fromIntegral $ unpack bs genSeedLength = Tagged 4 genBytes n g = Right $ genBytesHelper n empty g where genBytesHelper 0 partial gen = (partial, gen) genBytesHelper n partial gen = genBytesHelper (n-1)

Greetings, I have a game, and i want to save the objects ( creatues ) that move on canvas to a bundle so that when someone pauses/leaves the app, the objects can stay where they were. I have looked at the LunarLanding game where they save the coordinates of the space shuttle into bundles and read from them and i want to do same ( if there is no better way ) but i have objects of a custom type and i am not sure how to save them and read from the bundle. I could do the save of all the parts of the object individually and put them back together, but i have a lot of objects and that would just be

Would this work? class Cars{ Cars(int speed, int weight) } I am just trying to figure out the constructor. If it is called like a method then I thought it would work similar to a method. You can create local variables in a method that are used when that method is called so I don't see why instance variables have to be declared before constructors can use them. In your example speed and weight are not instance variables because their scope is limited to the constructor. You declare them outside in order to make them visible throughout the whole class (i.e. throughout objects of this class). The

Considering following struct and template function, does each use of the function with a different value for "num" build a new instance of the function or since const numbers<num> & nums parameter is a reference and would be implemented as a pointer all uses with different values for "num" can be directed to one instance of the function? template<size_t num> struct numbers{ public: unsigned int nums[num]; }; template<size_t num> void print(const numbers<num> & nums,size_t size){ for (int i=0;i<size;i++) cout <<nums.nums[i]<<' '; cout <<'\n'; } As far as you (the programmer) are concerned,

this is my code: private void MoveCursor(int x, int y) { // Set the Current cursor, move the cursor's Position, // and set its clipping rectangle to the form. System.Windows.Forms.Cursor cursorMouse = new System.Windows.Forms.Cursor(System.Windows.Forms.Cursor.Current.Handle); cursorMouse.Position = new System.Drawing.Point(x, y); System.Windows.Forms.Cursor.Clip = new System.Drawing.Rectangle(cursorMouse.Position, cursorMouse.Size); } This is what my console says: Error 11 Member 'System.Windows.Forms.Cursor.Position.get' cannot be accessed with an instance reference; qualify it with a type