javascript - Array.prototype.reject(): TypeError: ....reject is not a function -

i taking cool online course functional programming in javascript. following along fine until instructor used array.prototype.reject() , did not work me @ run time.

i use "reject" instead of loop because less code. but, browser, nodejs , express code consoles tell me reject not function.

i researched other articles discuss promise.reject not function, provide solutions not make sense scenario.

here example code in course:

var animals = [     { name: 'fluffykins',   species: 'rabbit' },     { name: 'caro',         species: 'dog' },     { name: 'hamilton',     species: 'dog' },     { name: 'harold',       species: 'fish' },     { name: 'ursula',       species: 'cat' },     { name: 'jimmy',        species: 'fish' } ];   var isdog = function(animal){     return animal.species === 'dog'; }  var otheranimals = animals.reject(isdog); 

the work-around for-loop:

var notdogs = animals.filter(function(animal){     return animal.species !== 'dog'; }); 

its output is:

> notdogs [ { name: 'fluffykins', species: 'rabbit' },   { name: 'harold', species: 'fish' },   { name: 'ursula', species: 'cat' },   { name: 'jimmy', species: 'fish' } ] 

please me use array.prototype.reject().

editl

i found array.prototype.reject() @ github/array.prototype.reject)

array.prototype.reject isn't thing unless library/custom code adds reject method arrays.

to achieve want, should use array.prototype.filter method are. i'm not sure think longer because can write same way:

var animals = [    { name: 'fluffykins', species: 'rabbit' },     { name: 'caro', species: 'dog' },     { name: 'jimmy', species: 'fish' }  ];    function nodogs(animal) {    return animal.species !== 'dog';  }    var otheranimals = animals.filter(nodogs);  console.log(otheranimals);