We are required to write a JavaScript function that takes in an array that contains elements of different data types and the function should return a map representing the frequency of each data type.
Let’s say the following is our array −
const arr = [23, 'df', undefined, null, 12, { name: 'Rajesh' }, [2, 4, 7], 'dfd', null, Symbol('*'), 8];
Example
Following is the code −
const arr = [23, 'df', undefined, null, 12, { name: 'Rajesh'}, [2, 4, 7], 'dfd', null, Symbol('*'), 8]; const countDataTypes = arr => { return arr.reduce((acc, val) => { const dataType = typeof val; if(acc.has(dataType)){ acc.set(dataType, acc.get(dataType)+1); }else{ acc.set(dataType, 1); }; return acc; }, new Map()); }; console.log(countDataTypes(arr));
Output
Following is the output in the console −
Map(5) { 'number' => 3, 'string' => 2, 'undefined' => 1, 'object' => 4, 'symbol' => 1 }