Intro To Ruby Notes -- W2D2

01_intro_to_ruby.rb

# string are processed literally inside computers
puts "Martin and Maggie are awesome co-workers!"

puts "here's another string"

# we can add numbers since they're the same type
puts 4 + 4

# we can add to strings (concat.) together to form a third string
puts 4.to_s + 8.to_s

# floats + integers result in floats
puts 42.9 + 50

# booleans are true or false values
# computers like booleans
puts false
puts true
puts true == false

02_basic_objects_and_variables.rb

name = "Sarah"
age = 24
my_var = "Female"
is_over_18 = true

puts name
puts name + " is " + age.to_s + " years old!"

name = "Jane"
puts name

03_string_interpolation.rb

name = "Sarah"
age = 24
my_var = "Female"
is_over_18 = true


# puts name + " is " + age.to_s + " years old!"
puts "#{name} is #{age} years old!"

04_control_flow.rb

name = "Sarah"
age = 24
my_var = "Female"
is_over_18 = (age > 19)

# a bouncer's logic
if is_over_18
	puts "#{name} is good to go in!"
	puts "Please pay entry fee!"
else
	puts "#{name} is underage!"
	puts "Ask them to leave!"
	age = 0
	if age > 0
		puts "Something isn't quite right."
	end
end

05_methods.rb

def overage_check(age, country)
	# ...
	# last line will always return
	if country == 'canada'
		age > 19
	else
		age > 18
	end
end

# a bouncer's logic
def bouncer_check(name, age)
	if overage_check(age, 'canada')
		puts "#{name} is good to go in!"
		puts "Please pay entry fee!"
	else
		puts "#{name} is underage!"
		puts "Ask them to leave!"
	end
end

name = "Sarah"
age = 24

name_2 = "Jackson"
age_2 = 18

bouncer_check(name, age)
bouncer_check(name_2, age_2)	

# method definition
# takes 2 params
def add(num1, num2)
  # returns the addition
  num1 + num2
end

# save the value of the response of the add method
# given params 5 and 7 into a variable named "added"
added = add(5, 7)

06_arrays_and_hashes.rb

# a method to check if a person passed as an argument has age of more than 19
def overage_check(person)
	if person[:age] > 19
		true
	else
		false
	end
end

# ARRAYS: for lists of things
list_of_nums = [1, "two", ["x", "y"], {key: "value"}]

list_of_nums.each do |current_number|
	puts "The current number is #{current_number}"
end

# print the first element of our array
# notice that the index starts at 0
puts list_of_nums[0]

# HASHES: for mixing data types
person_1 = {
	name: "Sarah",
	age: 24
}

person_2 = {
	name: "Jackson",
	age: 18
}

# AN ARRAY OF HASHES
people = [person_1, person_2]

# same as ...
people_2 = [{
	name: "Sarah",
	age: 24
}, {
	name: "Jackson",
	age: 18
}]

# How to access data from arrays and hashes
puts "Is #{person_1[:name]} underage? #{overage_check(person_1)}"
puts "Is #{people[0][:name]} underage? #{overage_check(people[0])}"