[Javascript] Advanced Reduce: Common Mistakes
Take away:
- Always check you ruturn the accumulator
- Always pass in the inital value
- var data = ["vote1", "vote2", "vote1", "vote2"];
- var reducer = function(acc, value){
- if(acc[value]){
- acc[value] = acc[value] + 1;
- }else{
- acc[value] = 1;
- }
- return acc;
- };
- var res = data.reduce(reducer ,{});
- console.log(res);
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