disjunkt-type-with-deep-tag.js

/* @flow */

type FooStyle = {
    style: {
        width: number,
    },
    data: {
        type: "foo"
    }
}

type BarStyle = {
    style: {
        height: number,
    },
    data: {
        type: "bar"
    }
}

type ElementStyle = FooStyle | BarStyle;

function process(ele: ElementStyle) {
    if (ele.data.type === "bar") {
        // This gives a flow error as height is not found in the object.
        console.log(ele.style.height);
    }
}