Function lazy

Make decoder that runs the given function and uses its result for decoding. This can be used for nested decoding, where you would otherwise get a Cannot access 'value' before initialization error.

Example

class Tree {}

const tree_decoder = Decode.instance(Tree, {
    value: Decode.field('value', Decode.integer),
    children: Decode.field(
        'children',
        Decode.lazy(() => Decode.many(tree_decoder)),
    ),
});

const raw = {
    value: 42,
    children: [
        { value: 43, children: [] },
        {
            value: 44,
            children: [
                { value: 45, children: [] },
            ],
        },
    ]
};

decode(tree_decoder, raw) // Decodes the nested tree structure
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