Passing Ruby Hash into Classes - ruby

Question

I ran into a study drill problem, and I couldn't figure it out.
Here's the link to the exercise. https://learnrubythehardway.org/book/ex40.html
Below are my work. On Study Drill 2, I passed in variables and it worked.
However, at study drill 3, I broke my code. I realized I wasn't passing in variable, but a hash. And because my class takes in 2 arguments, I couldn't figure out how to pass a dictionary as 2 arguments.
class Song
def initialize(lyrics, singer)
#lyrics = lyrics
#singer = singer
end
def sing_along()
#lyrics.each {|line| puts line}
end
def singer_name()
puts "The song is composed by #{#singer}"
end
def line_reader(lineNum)
line = #lyrics[lineNum-1]
puts "The lyrics line #{lineNum} is \"#{line}\"."
end
end
# The lyrics are arrays, so they have [] brackets
practiceSing = Song.new(["This is line 1",
"This is line 2",
"This is line 3"],"PracticeBand")
practiceSing.sing_along()
practiceSing.singer_name()
practiceSing.line_reader(3)
puts "." * 20
puts "\n"
# Variable for passing. Working on dictionary to pass the singer value.
lovingThis = {["Don't know if I'm right",
"but let's see if this works",
"I hope it does"] => 'TestingBand'}
# Everything after this line is somewhat bugged
# Because I was using a variable as an argument
# I couldn't figure out how to use dictionary or function to work with
this
practiceVariable = Song.new(lovingThis,lovingThis)
practiceVariable.sing_along()
practiceVariable.singer_name()
practiceVariable.line_reader(3)
Here's the Output. What it should do is return the singer/band, and return requested lyrics line.
I'm new to coding, please advise how to pass hashes into classes?
How to pass lovingThis hash into Song.new() and read as 2 arguments?

Answer 1

you can pass hash to constructor of class in the same way as we pass any other variable, But for that you need to change your constructor definition to take variable number of arguments i.e def initialize(*args)
class Song
def initialize(*args)
if args[0].instance_of? Hash
#lyrics = args[0].keys.first
#singer = args[0].values.first
else
#lyrics = args[0]
#singer = args[1]
end
end
def sing_along()
#lyrics.each {|line| puts line}
end
def singer_name()
puts "The song is composed by #{#singer}"
end
def line_reader(lineNum)
line = #lyrics[lineNum-1]
puts "The lyrics line #{lineNum} is \"#{line}\"."
end
end
# The lyrics are arrays, so they have [] brackets
practiceSing = Song.new(["This is line 1",
"This is line 2",
"This is line 3"],"PracticeBand")
practiceSing.sing_along()
practiceSing.singer_name()
practiceSing.line_reader(3)
puts "." * 20
puts "\n"
# Variable for passing. Working on dictionary to pass the singer value.
lovingThis = {["Don't know if I'm right",
"but let's see if this works",
"I hope it does"] => 'TestingBand'}
practiceVariable = Song.new(lovingThis)
practiceVariable.sing_along()
practiceVariable.singer_name()
practiceVariable.line_reader(3)