Syncs to August 5th

Author: yusufkaracin

tr-TR/README-tr_TR.md

@@ -2,7 +2,7 @@
 
 [Instagram](https://www.instagram.com/theavocoder) hesabımda, günlük olarak çoktan seçmeli Javascript soruları paylaşıyorum, ayrıca burada da paylaşacağım!
 
-Temelden ileri düzeye: Javascript'i ne kadar iyi bildiğinizi test edin, bilginizi biraz tazeleyin ya da mülakatanıza hazırlanın! :muscle: :rocket: Repoyu haftalık olarak yeni sorularla güncelliyorum. Son güncelleme: <a href=#20190726><b>26 Temmuz</b></a>
+Temelden ileri düzeye: Javascript'i ne kadar iyi bildiğinizi test edin, bilginizi biraz tazeleyin ya da mülakatanıza hazırlanın! :muscle: :rocket: Repoyu haftalık olarak yeni sorularla güncelliyorum. Son güncelleme: <a href=#20190805><b>5 Ağustos</b></a>
 
 Cevaplar, soruların altında gizlenmiştir. Görmek için sadece tıklayın. İyi şanşlar :heart:
 
@@ -2717,3 +2717,257 @@ function getName(name) {
 
 </p>
 </details>
+
+---
+
+###### <a name=20190805></a>87. Çıktısı Nedir?
+
+```javascript
+console.log("I want pizza"[0])
+```
+
+- A: `"""`
+- B: `"I"`
+- C: `SyntaxError`
+- D: `undefined`
+
+<details><summary><b>Cevap</b></summary>
+<p>
+
+#### Cevap: B
+
+Bir string içindeki belli bir indeksteki karakteri almak için, köşeli parantez notasyonunu kullanabilirsiniz. String içindeki ilk karakterin indeksi 0'dır, ve böylece devam eder. Bu örnekte indeksi 0 olan elemanı istiyoruz, `"I"` karakteri, loglanır.
+
+Bu yöntemin IE7 ve altında desteklenmediğine dikkat edin. Bu durumda, `.charAt()` kullanabilirsiniz.
+
+</p>
+</details>
+
+---
+
+###### 88. Çıktısı Nedir?
+
+```javascript
+function sum(num1, num2 = num1) {
+  console.log(num1 + num2)
+}
+
+sum(10)
+```
+
+- A: `NaN`
+- B: `20`
+- C: `ReferenceError`
+- D: `undefined`
+
+<details><summary><b>Cevap</b></summary>
+<p>
+
+#### Cevap: B
+
+You can set a default parameter's value equal to another parameter of the function, as long as they've been defined _before_ the default parameter. We pass the value `10` to the `sum` function. If the `sum` function only receives 1 argument, it means that the value for `num2` is not passed, amd the value of `num1` is equal to the passed value `10` in this case. The default value of `num2` is the value of `num1`, which is `10`.  `num1 + num2` returns `20`.
+
+If you're trying to set a default parameter's value equal to a parameter which is defined _after_ (to the right), the parameter's value hasn't been initialized yet, which will throw an error. 
+
+</p>
+</details>
+
+---
+
+###### 89. Çıktısı Nedir?
+
+```javascript
+// module.js 
+export default () => "Hello world"
+export const name = "Lydia"
+
+// index.js 
+import * as data from "./module"
+
+console.log(data)
+```
+
+- A: `{ default: function default(), name: "Lydia" }`
+- B: `{ default: function default() }`
+- C: `{ default: "Hello world", name: "Lydia" }`
+- D: Global object of `module.js`
+
+<details><summary><b>Cevap</b></summary>
+<p>
+
+#### Cevap: A
+
+With the `import * as name` syntax, we import _all exports_ from the `module.js` file into the `index.js` file as a new object called `data` is created. In the `module.js` file, there are two exports: the default export, and a named export. The default export is a function which returns the string `"Hello World"`, and the named export is a variable called `name` which has the value of the string `"Lydia"`. 
+
+The `data` object has a `default` property for the default export, other properties have the names of the named exports and their corresponding values. 
+
+</p>
+</details>
+
+---
+
+###### 90. Çıktısı Nedir?
+
+```javascript
+class Person {
+  constructor(name) {
+    this.name = name
+  }
+}
+
+const member = new Person("John")
+console.log(typeof member)
+```
+
+- A: `"class"`
+- B: `"function"`
+- C: `"object"`
+- D: `"string"`
+
+<details><summary><b>Cevap</b></summary>
+<p>
+
+#### Cevap: C
+
+Classes are syntactical sugar for function constructors. The equivalent of the `Person` class as a function constructor would be:
+
+```javascript
+function Person() {
+  this.name = name
+}
+```
+
+Calling a function constructor with `new` results in the creation of an instance of `Person`, `typeof` keyword returns `"object"` for an instance. `typeof member` returns `"object"`. 
+
+</p>
+</details>
+
+---
+
+###### 91. Çıktısı Nedir?
+
+```javascript
+let newList = [1, 2, 3].push(4)
+
+console.log(newList.push(5))
+```
+
+- A: `[1, 2, 3, 4, 5]`
+- B: `[1, 2, 3, 5]`
+- C: `[1, 2, 3, 4]`
+- D: `Error`
+
+<details><summary><b>Cevap</b></summary>
+<p>
+
+#### Cevap: D
+
+The `.push` method returns the _new length_ of the array, not the array itself! By setting `newList` equal to `[1, 2, 3].push(4)`, we set `newList` equal to the new length of the array: `4`. 
+
+Then, we try to use the `.push` method on `newList`. Since `newList` is the numerical value `4`, we cannot use the `.push` method: a TypeError is thrown.
+
+</p>
+</details>
+
+---
+
+###### 92. Çıktısı Nedir?
+
+```javascript
+function giveLydiaPizza() {
+  return "Here is pizza!"
+}
+
+const giveLydiaChocolate = () => "Here's chocolate... now go hit the gym already."
+
+console.log(giveLydiaPizza.prototype)
+console.log(giveLydiaChocolate.prototype)
+```
+
+- A: `{ constructor: ...}` `{ constructor: ...}` 
+- B: `{}` `{ constructor: ...}` 
+- C: `{ constructor: ...}` `{}`
+- D: `{ constructor: ...}` `undefined`
+
+<details><summary><b>Cevap</b></summary>
+<p>
+
+#### Cevap: D
+
+Regular functions, such as the `giveLydiaPizza` function, have a `prototype` property, which is an object (prototype object) with a `constructor` property. Arrow functions however, such as the `giveLydiaChocolate` function, do not have this `prototype` property. `undefined` gets returned when trying to access the `prototype` property using `giveLydiaChocolate.prototype`. 
+
+</p>
+</details>
+
+---
+
+###### 93. Çıktısı Nedir?
+
+```javascript
+const person = {
+  name: "Lydia",
+  age: 21
+}
+
+for (const [x, y] of Object.entries(person)) {
+  console.log(x, y)
+}
+```
+
+- A: `name` `Lydia` and `age` `21`
+- B: `["name", "Lydia"]` and `["age", 21]` 
+- C: `["name", "age"]` and `undefined`
+- D: `Error`
+
+<details><summary><b>Cevap</b></summary>
+<p>
+
+#### Cevap: A
+
+`Object.entries(person)` returns an array of nested arrays, containing the keys and objects:
+
+`[ [ 'name', 'Lydia' ], [ 'age', 21 ] ]` 
+
+Using the `for-of` loop, we can iterate over each element in the array, the subarrays in this case. We can destructure the subarrays instantly in the for-of loop, using `const [x, y]`. `x` is equal to the first element in the subarray, `y` is equal to the second element in the subarray. 
+
+The first subarray is `[ "name", "Lydia" ]`, with `x` equal to `"name"`, and `y` equal to `"Lydia"`, which get logged.
+The second subarray is `[ "age", 21 ]`, with `x` equal to `"age"`, and `y` equal to `21`, which get logged.
+
+</p>
+</details>
+
+---
+
+###### 94. Çıktısı Nedir?
+
+```javascript
+function getItems(fruitList, ...args, favoriteFruit) {
+  return [...fruitList, ...args, favoriteFruit]
+}
+
+getItems(["banana", "apple"], "pear", "orange")
+```
+
+- A: `["banana", "apple", "pear", "orange"]`
+- B: `[["banana", "apple"], "pear", "orange"]` 
+- C: `["banana", "apple", ["pear"], "orange"]`
+- D: `SyntaxError`
+
+<details><summary><b>Cevap</b></summary>
+<p>
+
+#### Cevap: D
+
+`...args` is a rest parameter. The rest parameter's value is an array containing all remaining arguments, **and can only be the last parameter**! In this example, the rest parameter was the second parameter. This is not possible, and will throw a syntax error. 
+
+```javascript
+function getItems(fruitList, favoriteFruit, ...args) {
+  return [...fruitList, ...args, favoriteFruit]
+}
+
+getItems(["banana", "apple"], "pear", "orange")
+```
+
+The above example works. This returns the array `[ 'banana', 'apple', 'orange', 'pear' ]`
+</p>
+</details>