JSFiddle - React, Tailwind, and code Playground

JavaScript

var x = [{ a: 1, b: 2}, { a: 11, b: 12}, { a: 31, b: 23}, { a: 51, b: 24}], tocomp = 11;
var res = x.filter(function(val, _){
    return val.a === tocomp; 

});
console.log(res);