8. Pattern Matching As Functions You can alsopass pattern matching as a parameter to other methods. Scala compiles a pattern match down to aPartialFunction[A,B], which is a subclass of Function1[A,B].So a pattern can be passed to any method that takes a single parameter function. This...
the next example shows how several different functions are passed into a function namedsum(). As you can see from the definition of the sum function, its first argument is a function which it namesf, and that function takes one Int as a parameter, and returns anIntas a function result: ...
So the issue is how can you pass a by-name-parameter to a method that takes a function as a parameter without having to do: 1. scala> def takesFunc(func: () => Int) = println(func()) 2. takesFunc: (() => Int)Unit 3. scala> def send(x: => Int) = takesFunc(() => x...
If you pass the type parameters ofMap[Int, String]all the way down the chain, we find that the types passed toTraversableLike, and, thus, used bymap, are: A=(Int,String) Repr=Map[Int,String] Going back to the example, the first map is receiving a function of type((Int, String))...
We have apowerfunction. The function has one argument with an implicit value. We can call the function with one or two arguments. def power(x: Int, n: Int = 2): Int = The second parameter of thepowerfunction is implicit. If it is not provided, its value is 2. ...
This example demonstrated how to pass an existing function as a parameter to a higher-order function. An alternative to using functions as parameters is to define them inline with function literals, as we will see in the next section.
The default values from consecutive groups can refer to the parameters defined in previous groups as e refers to the default value of c, which is a.The type of the value parameter prefixed with => means that this parameter should not be evaluated at the moment the method is called, but ...
Call by name is used in Scalawhen the program needs to pass an expression or a block of code as a parameter to a function. The code block passed as call by name in the program will not get executed until it is called by the function. ...
It doesn't matter where a Value.Str came from: whether a literal Expr.Str in the source code, passed in as a function parameter to a Expr.Func, or bound to a local variable via Expr.Local, it is still the same Value.Str. The final Value for the entire Jsonnet program is then ...
If the value we want to pass to the function is already calculated, using parentheses to specify the function parameter is the natural way to go. But if you have calculations that will only be used for the function, and you can keep the code readable to others, a function invocation with...