how to map a var to a function in javascript code example

Example 1: javascripr array.map

array.map( item => item.id )

array2.map( item => item.toString() )

array2.map( item => item * 3 )

// this will apply a transformation to all elements of an array
// "" item => something "" is the transformation (function)

Example 2: array map

let A = [{ x:'x', y:'y' }, { x:'x', y:'y' }];

let result = A.map(({y,...rest})=> ({...rest,v:y}));

console.log(result);