#generic type constructor method

1 messages · Page 1 of 1 (latest)

ionic silo
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i don't understand why this doesn't count as correct syntax, it looks the same to me as what is listed on the java reference page for generic methods

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night gulchBOT
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<@&987246399047479336> please have a look, thanks.

ionic silo
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oh wiat nvm

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sorry for the ping i figured it out lol

livid cargo
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that is done either on class level or on method level

livid cargo
ionic silo
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wait so this doesnt work?

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raven lichen
ionic silo
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public class Point {
    public double x;
    public double y;

    public Point(){
        x = 0;
        y = 0;
    }

    public Point(double x, double y){
        this.x = x;
        this.y = y;
    }

    public String toString(){
        Double X = x;
        Double Y = y;
        return "(" + X.toString() + "," + Y.toString() + ")";
    }

    public void print(){
        System.out.print(this.toString());
    }

    public static void main(String[] args) {
        Point a = new Point(3,2);
        a.print();
    }
}``` i ended up ditching generics because i couldnt cast an Integer to a Double
night gulchBOT
raven lichen
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And constructors are going to be different than other methods

raven lichen
ionic silo
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so i'm letting implicit conversion do its thing

raven lichen
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You can definitely do this with generics, but you need to make the class itself generic too and to make that function properly you'll need to make some unifying abstraction over ints and doubles which doesn't always exist

ionic silo
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and which is way beyond me anyways lol

raven lichen
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You can make a generic pair class

ionic silo
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probably way beyond what i'll even touch on this semester

raven lichen
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That's easier - but it only makes sense if you don't need to do any common operations on the actual thing within the pair

ionic silo
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this is where operator overloading would be great so i could add points with + and do 2D vector arithmetic without calling extremely verbose methods

raven lichen
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Well operator overloading is only one part of that

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Even before you make it so that the plus sign magically calls a method you need to define that method

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And that's the part where we're having a bit of an issue

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Because what the heck do you do to define Point<T> add(Point<T> a, Point<T> b)

ionic silo
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i see

raven lichen
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Operator overloading is finally on the table in one way or another, but you'll still have this problem

unborn vine
unborn vine