tjcafferkey / removeduplicates Goto Github PK

function removeDuplicates(arr, key) { if (!(arr instanceof Array) || key && typeof key !== 'string') { return false; } if (key && typeof key === 'string') { return arr.filter((obj, index, arr) => { return arr.map(mapObj => mapObj[key]).indexOf(obj[key]) === index; }); } else { return arr.filter(function(item, index, arr) { return arr.indexOf(item) == index; }); } }

I can't run function on IE 11 (error messsage : Syntax error).
Something wrong in this code

return arr.filter((obj, index, arr) => { return arr.map(mapObj => mapObj[key]).indexOf(obj[key]) === index; });