Array Object Methods - 1
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/*
Arrays are hugely useful in any programming language, and JavaScript is no
exception. JavaScript includes a variety of built-ins to help with arrays.
*/
var array = [1, 2, 3, 4];
// unshift(value) places the argument at the beginning of the array
array.unshift(0);
// push(value) places the argument at the end of the array
array.push(5);
// shift() gets the first value of the array and returns it
array.shift();
// pop() gets the last value of the array and returns it
array.pop();
// find(function(object)) finds the value in the array that matches the test and returns that *value*
// this is an ES6 function, so using it with node or modern browsers requires extensions or transpiling
// findIndex(function(object)) does the same thing as find(), but returns the *index*
/*
function is_three(value) {
return value === 3;
}
array.find(is_three);
*/
// reduce(function(object)) applies a function to all values in the array to reduce it a single value
function sum(a, b) {
return a + b;
}
array.reduce(sum);
JavaScript
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