feat added variouse arrray iterators

Array Methods/filter.js

@@ -0,0 +1,21 @@
+ filter
+// does return a new array
+// can manipulate the size of new array
+// returns based on condition
+
+const people = [
+  { name: 'bob', age: 20, position: 'developer' },
+  { name: 'peter', age: 25, position: 'designer' },
+  { name: 'susy', age: 30, position: 'the boss' },
+  { name: 'anna', age: 35, position: 'the boss' },
+];
+
+const youngPeople = people.filter(function (person) {
+  return person.age <= 25;
+});
+
+const developers = people.filter(function (person) {
+  return person.position === 'senior developer';
+});
+
+console.log(developers);

Array Methods/forEach.js

@@ -0,0 +1,18 @@
+// forEach
+// does not return new array
+
+const people = [
+  { name: 'bob', age: 20, position: 'developer' },
+  { name: 'peter', age: 25, position: 'designer' },
+  { name: 'susy', age: 30, position: 'the boss' },
+];
+
+function showPerson(person) {
+  console.log(person.position.toUpperCase());
+}
+
+// people.forEach(showPerson);
+
+people.forEach(function (item) {
+  console.log(item.position.toUpperCase());
+});

Array Methods/map.js

@@ -0,0 +1,29 @@
+// map
+// does return a new array
+// does not change size of original array
+// uses values from original array when making new one
+
+const people = [
+  { name: 'bob', age: 20, position: 'developer' },
+  { name: 'peter', age: 25, position: 'designer' },
+  { name: 'susy', age: 30, position: 'the boss' },
+  { name: 'anna', age: 35, position: 'the boss' },
+];
+
+const ages = people.map(function (person) {
+  return person.age + 20;
+});
+const newPeople = people.map(function (person) {
+  return {
+    firstName: person.name.toUpperCase(),
+    oldAge: person.age + 20,
+  };
+});
+
+const names = people.map(function (person) {
+  return `<h1>${person.name}</h1>`;
+});
+
+document.body.innerHTML = names.join('');
+
+console.log(names);