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This should be an easy one. How do I apply a function to a tuple in Scala? Viz:
scala> def f (i : Int, j : Int) = i + j f: (Int,Int)Int scala> val p = (3,4) p: (Int, Int) = (3,4) scala> f p :6: error: missing arguments for method f in object $iw; follow this method with `_' if you want to treat it as a partially applied function f p ^ scala> f _ p :6: error: value p is not a member of (Int, Int) => Int f _ p ^ scala> (f _) p :6: error: value p is not a member of (Int, Int) => Int (f _) p ^ scala> f(p) :7: error: wrong number of arguments for method f: (Int,Int)Int f(p) ^ scala> grr!
Many thanks in advance.
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Use Concatenation + to Append to a Tuple in Python Much like strings, tuple values can be altered or appended by simply concatenating a new value onto the existing one. It combines two different sets of tuples into one and doesn't actually change existing values, maintaining the immutability of the data type.
The Python tuple() function is a built-in function in Python that can be used to create a tuple. A tuple is an ordered and immutable sequence type.
Functions can return tuples as return values.
Python tuple is an immutable object. Hence any operation that tries to modify it (like append) is not allowed. However, following workaround can be used.
scala> def f (i : Int, j : Int) = i + j f: (i: Int,j: Int)Int // Note the underscore after the f scala> val ff = f _ ff: (Int, Int) => Int = <function2> scala> val fft = ff.tupled fft: ((Int, Int)) => Int = <function1> scala> def f (i : Int, j : Int) = i + j f: (Int,Int)Int // Note the underscore after the f scala> val ff = f _ ff: (Int, Int) => Int = <function> scala> val fft = Function.tupled(ff) fft: ((Int, Int)) => Int = <function> If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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