Java 9 features announced

Re:Java 9 features announced by wyager on Monday August 18, 2014 @04:24PM (#8194444)

Not exactly comparable (because everything is immutable), but Haskell has sort of a cool approach to setting and getting fields.

Let's say you have

    data Point = Point {x :: Int, y :: Int}

If you have a Point object called "point", you can get x by doing

    x_coord = x point

If you want to create a new Point with x set to 5, you can do

    point' = point {x = 5}

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Re:Java 9 features announced by vishbar on Tuesday August 19, 2014 @06:00AM (#8196605)

F# has a similar concept via the with statement. To use your example:

    type point = { x: int; y:int}
    let z = {x = 5; y = 10} 
    let y = {z with x = 17}

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Re:Java 9 features announced by virtualwhys on Tuesday August 19, 2014 @06:45AM (#8196691)

Interesting, Scala equivalent is:

    case class Point(x: Int, y: Int)
    val p1 = Point(5,10)
    val p2 = p1.copy(x=17)

How does F# handle nested data types? In Scala if you want to copy a case class of a case class (of a case class ...) it can get boilerplate-y as you have to copy outside-in through each property a la:

    x.copy(acase.copy(bcase.copy(cprop=1)))

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