Es6

Question 1

What is a code block? What are some examples of a code block?

Answer 1

if statement, loops, functions / code block {}

Question 2

What does block scope mean?

Answer 2

variable defined within a block {} can not be accessed outside of the block

Question 3

What is the scope of a variable declared with “const” or “let”?

Answer 3

block scope, var is a function scope

Question 4

Why is it possible to .push() a new value into a const variable that points to an array?

Answer 4

const is storing a reference to the array, you’re not modifying the array

Question 5

How should you decide which type of declaration to use?

Answer 5

Use Let if you want the variable to be mutable, use Const if variable can not be reassigned

Question 6

What is the difference between Let and Const?

Answer 6

Use Let if you want the variable to be mutable, use Const if variable can not be reassigned

Question 7

What is the syntax for writing a template literal?

Answer 7

using backticks `, \n\ for multi-line (when escaping to the next line), ${variableName}

Question 8

What is “string interpolation”?

Answer 8

string formatting so that we can substitute a part of the string for values of variables or expressions

Question 9

What is destructuring, conceptually?

Answer 9

taking apart something

Question 10

What is the syntax Object destructuring?

Answer 10

const, opening curly brace, name of property, closing curly brace, assigned to the object

Question 11

What is the syntax for Array destructuring?

Answer 11

const, [variables, variables, variables] assigned to arrayName

Question 12

How can you tell the difference between destructuring and creating Object/Array literals?

Answer 12

var/const/let {} = objectName, var/const/let []= arrayName

Question 13

What is the syntax for defining an arrow function?

Answer 13

=>

Question 14

When an arrow function’s body is left without curly braces, what changes in its functionality?

Answer 14

With {}, there must be a return statement, without just defines an arrow function. => expression VS. => { statements }

Question 15

How is the value of this determined within an arrow function?

Answer 15

where the function is defined

Question 16

What is a CLI?

Answer 16

command-line interfaces processes commands to a computer program using lines of text. Examples of this are text-based user interfaces and keyboard shortcuts

Question 17

What is a GUI?

Answer 17

graphical user interface, allows users to interact w/ devices through graphical icons and audio indicators instead of text-based user interfaces, typed command labels or text navigation

Question 18

Give at least one use case for each of the commands listed in this exercise.

Answer 18

man = to see the system reference manuals, ex. find the manual for executable programs or shell commands 
cat = concatenate files and print on the standard output, ex.-n, --number makes number all outputlines
ls = list directory contents q
pwd = print name of current/working directory
echo = display a line of text
touch = changes file timestamp
mkdir = make directories
mv = move (rename) files
rm = remove files and directories
cp = copy files and directories
history = show GNU history library

Question 19

What are the three virtues of a great programmer?

Answer 19

laziness, impatience, and hubris