JavaScript Functional Library Project Submission

index.js

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+//Collection Functions (Arrays or Objects)
+
+const myEach = (collection, callback) => {
+  if (Array.isArray(collection)) {
+    for (let i = 0; i < collection.length; i++) {
+      callback(collection[i])
+    }
+  } else {
+    for (let key in collection) {
+      callback(collection[key])
+    }
+  }
+  return collection
+}
+
+const myMap = (collection, callback) => {
+  const mapArray = []
+
+  myEach(collection, (item, index, collection) => {
+      mapArray.push(callback(item, index, collection))
+  })
+
+  return mapArray
+}
+
+const myReduce = (collection, callback, acc) => {
+
+  const objectValues = []
+
+  if (!Array.isArray(collection)) {
+    for (let key in collection) {
+      objectValues.push(collection[key])
+    }
+    collection = objectValues
+  }
+
+  if (!acc) {
+      acc = collection[0]
+
+      myEach(collection.slice(1), (value) => {
+        acc = callback(acc, value)
+      })
+      return acc
+    }
+  myEach(collection, (value) => {
+    acc = callback(acc, value)
+  })
+
+  return acc
+
+}
+
+const myFind = (collection, predicate) => {
+  for (let i = 0; i < collection.length; i++) {
+    if (predicate(collection[i])) {
+      return collection[i];
+    }
+  }
+  return undefined
+}
+
+const myFilter = (collection, predicate) => {
+  const filteredArray = []
+
+  for (let i = 0; i < collection.length; i++) {
+    if (predicate(collection[i])) {
+      filteredArray.push(collection[i])
+    }
+  }
+
+  return filteredArray
+}
+
+const mySize = collection => {
+
+  const objectKeys = []
+
+  if (!Array.isArray(collection)) {
+    for (let key in collection) {
+      objectKeys.push(key)
+    }
+    collection = objectKeys
+  }
+
+  return collection.length
+}
+
+
+//Array Functions
+
+const myFirst = (array, n) => {
+  if (n) {
+    return array.slice(0, n)
+  }
+  return array[0]
+}
+
+const myLast = (array, n) => {
+
+  if (n) {
+    return array.slice(-n)
+  }
+  return array[mySize(array)-1]
+}
+
+const mySortBy = (array, callback) => {
+  return [...array].sort((a, b) => {
+    const valA = callback(a);
+    const valB = callback(b);
+
+    if (typeof valA === 'string' && typeof valB === 'string') {
+      return valA.localeCompare(valB);
+    }
+
+    return valA - valB;
+  })
+}
+
+const myFlatten =  (array, [shallow], newArr=[]) => {
+
+}
+
+//Object Functions
+
+const myKeys = object => {
+  const keys = []
+
+  for (let key in object) {
+    keys.push(key)
+  }
+  return keys
+}
+
+const myValues = function (object) {
+  const values = []
+
+  for (let key in object) {
+    values.push(object[key])
+  }
+  return values
+}