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Ruby Ruby Basics Conditionals A Better "check_speed" Method

Posted by David Wilson
David Wilson
7,073 Points

A Better "check_speed" Method

This seems like it should work? What am I missing?

program.rb 
def check_speed(speed)
  if speed < 45
    puts "too slow"
  elsif speed > 60
    puts "too fast"
  else speed.between(45, 60)
    puts "speed OK"
  end
end

4 Answers

William Li
PLUS
William Li
Courses Plus Student 26,868 Points
William Li
William Li
Courses Plus Student 26,868 Points

Your code only requires a small fix to make it work. The syntax error lies on this line else speed.between(45, 60), as Antonio De Rose has pointed out, unlike if & elsif clause, else clause does not follow up w/ a conditional check. So delete speed.between(45, 60) after the else keyword, and your code should pass.

def check_speed(speed)
  if speed < 45
    puts "too slow"
  elsif speed > 60
    puts "too fast"
  else            # deleted speed.between(45, 60)
    puts "speed OK"
  end
end

In fact, it makes perfect sense to write the code this way, because if the number is greater than 45 & less than 60, it must lie somewhere between (45, 60).

Antonio De Rose
Antonio De Rose
20,884 Points
Antonio De Rose
Antonio De Rose
20,884 Points 
def check_speed(speed)
  if speed < 45
    puts "too slow"
  elsif speed > 60 # it is a good practice, to follow in a top down approach, like
#when you check for the conditions
#first 45 then between 45 and 60 and then finally, 60 above
    puts "too fast"
  else speed.between(45, 60) #error, you do not have something like between with argument passed for an if else
#and else cant have a condition, it literally an else and no paranthasis with a conditon
#meaning, anything of all the above conditions, go into this scope
    puts "speed OK"
  end
end

#you can either have 3 separate if's, for the reason, there is nothing can be with an else condition
#or else, you can have one if and 2 elsif's which I will not encourage, as there will be an else part missing

#like the below

def check_speed(speed)
  if speed  < 45
    puts "too slow"
  end
  if speed >= 45 and speed <= 60 
    puts "speed OK"
  end
  if speed > 60
    puts "too fast"
  end
end
David Wilson
David Wilson
7,073 Points
David Wilson
David Wilson
7,073 Points

Thank you both.

Michael Lazarz
Michael Lazarz
15,135 Points
Michael Lazarz
Michael Lazarz
15,135 Points

This is what I have. In my editor it works, however in workspaces it does not. Am I missing something in translation?

def check_speed(speed)
    if speed >= 60
        puts "too fast"
    elsif speed > 45
        puts "speed OK"
    else
        puts "too slow"
    end
end

check_speed(45)      # Returns 'too slow'
check_speed(46)      # Returns 'speed OK'
check_speed(60)      # Returns 'too fast'