Dynamic constant assignment Ruby [duplicate] - ruby

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Dynamic constant assignment
(7 answers)
Closed 2 years ago.
I have been following a tutorial to create a typing challenge. I have taken care to follow this carefully. When i try to run the script from the command line i keep getting the following error and i do not understand it. I think the tutorial might be quite old but if someone could give me some guidance to understand it so i can fix it then that would be so appreciated! The error i get when i run the script from the command line is as follows....
Typechallenge.rb:89: dynamic constant assignment
Console_Screen = Screen.new
^
typechallenge.rb:90: dynamic constant assignment
Typing_Test = Test.new
The script itself is below...
#Script name: Typing Challenge
#Description: Demonstrating how to apply conditional logic in order to analyze user input and control
#the execution of the script through a computer typing test.
class Screen
def cls
puts ("\n" * 25)
puts "\a"
end
def pause
STDIN.gets
end
end
class Test
def display_greeting
Console_Screen.cls
print "\t\t Welcome to the Typing Challenge" +
"\n\n\n\n\n\n\n\n\n\n\n\n\nPress Enter to " +
"continue. \n\n: "
Console_Screen.pause
end
def display_instructions
Console_Screen.cls
puts "\t\t\tInstructions:\n\n"
puts %Q{ This test consists of five typing challenges. Each sentence is a challenge and are presented one at a time. To respond
correctly you should retype each sentence exactly as it is shown and the press the Enter key. Your grade will be displayed at
the end of the test.\n\n\n\n\n\n\n\n\n
Press Enter to continue.\n\n}
Console_Screen.pause
End
def present_test(challenge)
Console_Screen.cls
print challenge + "\n\n: "
result = STDIN.gets
result.chop!
if challenge == result then
$noRight += 1
Console_Screen.cls
print "Correct!\n\nPress Enter to continue."
Console_Screen.pause
else
Console_Screen.cls
print "Incorrect!\n\nPress Enter to continue."
Console_Screen.pause
end
end
def determine_grade
Console_Screen.cls
if $noRight >= 3 then
print "You retyped " + $noRight.to_s + " sentence(s) correctly. "
puts "You have passed the typing test!\n\nPress Enter to continue."
else
print "You retyped " + $noRight.to_s + " sentence(s) correctly. "
puts "You have failed the typing test!\n\nPress Enter to continue."
end
end
#Main script logic
$noRight = 0
Console_Screen = Screen.new
Typing_Test = Test.new
Typing_Test.display_greeting
Console_Screen.cls
print "Would you like to test your typing skills? (y/n)\n\n: "
answer = STDIN.gets
answer.chop!
until answer == "y" || answer == "n"
Console_Screen.cls
print "Would you like to test your typing skills? (y/n)\n\n: "
answer = STDIN.gets
answer.chop!
end
#Analyzing the players response
if answer == "n"
Console_Screen.cls
puts "Okay, perhaps another time! \n\n"
else
Typing_Test.display_instructions
Typing_Test.present_test "In the end there can be only one"
Typing_Test.present_test "Once upon a time a great plague swept across the land"
Typing_Test.present_test "Welcome to the typing challenge"
Typing_Test.present_test "There are very few problems in the world" + "that enough M&Ms cannot fix."
Typing_Test.present_test "Lets play this game of life together"
Typing_Test.determine_grade
Console_Screen.pause
Console_Screen.cls
puts "Thank you for playing the game!\n\n"
end
end
end

Answer 1

Names that start with upper-case letter are constants. In your code you assign a non-constant (dynamic) value to a name that represents a constant. Hence the error.
Console_Screen = Screen.new
Use local variable name convention (snake_case)
console_screen = Screen.new