gistfile1.txt

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<!-- language: lang-js -->

    const one = [
        {
            name: 'CRISPS', items: [{ name: 'salty crisps',items: [] }]
        },
        {
            name: 'CHOCOLATE', items: [{ name: 'full sized bars', items: [] }]
        }
    ]

    const two = [
        {
            name: 'CRISPS',  items: [{ name: 'salty crisps',items: [] }]
        },
        {
            name: 'DRINKS', items: [{ name: 'fizzy drinks',items: [] }]
        },
{
            name: 'CHOCOLATE', items: [{ name: 'small sized bars', items: [] }]
        }
    ]

    const merge = (p, ...arrs) => [...new Set([].concat(...arrs).map(a => JSON.stringify(a)))].map(a => JSON.parse(a));

    const three = merge('name', one, two);

    console.log(three);

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