This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center.
Closed 9 years ago.
I am stuck with a program that won't run properly. Here is my code:
puts '<Input greeting below>'
answer = gets.chomp
if answer == 'Hello' || 'Hi'
answer == true
else
answer == false
puts 'Hey, how are you?'
answer2 = gets.chomp
if answer2 == 'I\'m good' || 'I\'m doing well'
answer2 == true
else
answer2 == false
puts 'That\'s good. Would you like to know facts about ruby programming?'
answer3 = gets.chomp
if answer3 == 'Sure'
answer3 == true
else
answer3 == false
puts 'Ok, well did you know that {hello, world} was the first program ever made?'
answer4 = gets.chomp
if answer4 == 'Yes'
answer4 == true
else
answer4 == false
puts 'Wow, you\'re pretty good! Would you like to know another fact?'
answer5 = gets.chomp
if answer5 == 'Sure'
answer5 == true
else answer5 == false
puts 'Alright, did you know the programming language "Ruby"
was developed by a Japanese techonolgist named "Yukihiro Matsumoto"
because he wasn\'t satisfied with the other programming languages?'
end
end
end
end
end
Windows CMD says that I have a problem on line 29 with the "end" part. I can't figure it out. Can someone please help?
You've got a number of problems here that need to be fixed before you can get a working program.
First up, if x == A || B does not mean what you think it does. This evaluates to if x == (A || B) where it will only compare to the first string, not the second. To test against multiple possible matches the best approach is to use case:
case (answer)
when 'Hello', 'Hi'
# Matches!
else
# Not matched
end
You can also break out several different conditions by adding additional when clauses, and you can even use regular expressions to catch variations in case, and so forth.
As I added in a comment, this nested if pattern needs to go away. You need to switch to a state system instead:
state = :greeting
loop do
case (state)
when :greeting
puts "<input greeting below>"
case (gets.chomp)
when "Hello", "Hi"
state = :how_are_you
else
break
end
when :how_are_you
puts "Hey, how are you?"
case (gets.chomp)
when "I'm good", "I'm doing well"
state = :thats_good
else
break
end
# ... Additional `when` clauses.
end
end
Related
I am new to Ruby. I have written the code below, its working about 90% except the else statement. The else statement triggers endless loop. I just want it to ask user to try again. Here is my code
puts "Do you want to print something? (Y / N)"
user = gets.chomp.downcase
answer = true
while answer
if user == "y"
puts "Something"
answer = false
elsif user == "n"
puts " "
answer = false
else
puts "Invalid input! Please enter Y or N"
end
end
Somewhat shorter (note user has gone, the answer is now referred to as answer).
answer = ""
until (answer == "y") or (answer == "n")
puts 'Do you want to print something? (Y/N)'
answer = gets.chomp.downcase
end
Once you exit the else, answer is still true. If you want to re-prompt, you can move your puts and user statement into the loop.
Something like this should work.
while true # (alternately) loop do
puts 'Do you want to print something? (Y/N)'
case gets.chomp.downcase
when 'y'
puts 'foo'
break
when 'n'
puts 'bar'
break
else
puts 'Invalid input! Please enter Y or N'
end
end
You can use break to exit out of your loop instead of setting up another variable. Also, this looks like a good use-case for a case statement to have some explicit cases listed.
I am just starting with ruby and tried to create a multiple choice game. I can't seem to see where i get something wrong which makes it so that it either repeats the generic line for a room instead of showing the resulting option.
just for info, the options in the hall are either "north", "look" or "quit"
then in the study, options are "look", "look at desk", "south", "quit", "enter combination 2451"
code below:
def hall_begin
#first line you see
puts "you can either look around or move north"
gets.chomp
end
def look_hall
# first option to look around in the hall
puts "You are standing in a hall with a marble floor. You see a door."
hall_begin
end
def onwards_study
# second option to go forwards into the next room from the hall
puts "You are in the study, you can either look around of move back south"
gets.chomp
end
def back_to_hall
# moving back into the hall from the study
puts "You are back in the hall, either look around or go north"
gets.chomp
end
def look_study
# looking around the study to find the desk and safe
puts "You are in a warm and cosy study. You see a safe. You see a desk."
onwards_study
end
def study_desk
# looking on the study desk to find the combination
puts "You see a piece of paper that reads, The combination is 2451."
onwards_study
end
def study_safe
# if you open the safe with combination
puts "You see some diamonds in the safe, pick them up and make your escape"
end
def first_choice
# all the choices whilst in the hall
while true
direction_1 = hall_begin
if direction_1 == "look"
look_hall
elsif direction_1 == "north"
onwards_study
elsif direction_1 == "quit"
break
end
end
end
while true
# start of the game
first_choice
while true
# all choices you face whilst in the study
direction_2 = onwards_study
if direction_2 == "look"
look_study
elsif direction_2 == "south"
back_to_hall
elsif direction_2 == "look at desk"
study_desk
elsif direction_2 == "enter combination 2451"
study_safe
break
elsif direction_2 == "quit"
break
end
break
end
end
This seems to be a beginner level program. In case if you haven't studied the functions yet. This simple code can help you.
won_condition = false
breaking_condition = false
puts "You are standing in the hall, either look around or go north"
while true
if won_condition == true
break
end
if breaking_condition == true
break
end
user_input = gets.chomp
if user_input == 'quit'
break
elsif user_input == "look"
puts "You are standing in a hall with a marble floor. You see a door."
elsif user_input == 'north'
puts "You are in the study, you can either look around or move back south"
while true
study_input = gets.chomp
if study_input == 'look'
puts "You are in a warm and cosy study. You see a safe. You see a desk."
elsif study_input == 'look at desk'
puts "You see a piece of paper that reads, The combination is 2451."
elsif study_input == 'south'
puts "You are standing in the hall, either look around or go north"
break
elsif study_input == '2451'
puts "You see some diamonds in the safe, pick them up and make your escape."
won_condition = true
break
elsif study_input == 'quit'
breaking_condition = true
break
end
end
end
end
As Chandan pointed out, having this many loops is unnecessary. I think what you are after can be achieved by having one main loop that gets the user input and then handles it.
I don't want to make too complicated suggestions to begin with since you are just starting out, but I think keeping track of a "current_room" variable is helpful (which can later transition into coordinates on a 2D room array or something).
Too give you a few examples, this is how something similar could be achieved.
def describe_room(current_room)
if current_room == "hall"
puts "You are standing in the hall, either look around or go north"
elsif current_room == "study"
puts "You are in the study, you can either look around of move back south"
end
end
def examine_room(current_room)
if current_room == "hall"
puts "You are standing in a hall with a marble floor. You see a door."
elsif current_room == "study"
puts "You are in a warm and cosy study. You see a safe. You see a desk."
end
end
def move(current_room, direction)
if current_room == "hall" and direction == "north"
"study"
elsif current_room == "study" and direction == "south"
"hall"
else
puts "You cannot go that way"
current_room
end
end
def hall_commands(command)
# No hall specific commands at this points
puts "Unknown command"
# Return "hall" since we are never moving anywhere else
"hall"
end
def study_commands(command)
if command == "look at desk"
puts "You see a piece of paper that reads, The combination is 2451."
elsif command == "enter combination 2451"
puts "You see some diamonds in the safe, pick them up and make your escape"
return nil # Use explicit return statement to avoid default return at the end of the method
else
puts "Unknown command"
end
# Return "study" as the default
"study"
end
# Starting position
current_room = "hall"
while true
break if current_room == nil
# Start each loop by a brief description of the current room.
describe_room(current_room)
# Get the user input in the main loop
command = gets.chomp
# Check for global commands (i.e. movements, look, etc.) first
# and then move on to check for room specific commands.
if command.in?(["north", "east", "south", "west"])
current_room = move(current_room, command)
elsif command == "look"
examine_room(current_room)
elsif command == "quit"
break
elsif current_room == "hall"
current_room = hall_commands(command)
elsif current_room == "study"
current_room = study_commands(command)
else
puts "Unknown command"
end
end
Basically I have simplified it into one loop as mentioned earlier, then split up the "global commands" that could be used regardless which room your are in, and the "room specific commands" that only apply in certain rooms.
I hope this helps you getting into Ruby. When you feel more comfortable, I would recommend looking into case/when statements as an alternative to if/elsif/else statements and also Arrays to keep track of rooms and positions.
I have a small code for determining the number of hours per year.
What I am looking for is for a Ruby way to allow different user's input options for all possible valid answer stored in an array
to check if the user provided a valid option by calling include? on the array.
When year consist of 52 weeks.
Week consists of 7 days.
Day consists of 24 hours
My problem comes up when trying to pass different answers for the gets method such as follows:
if answer == "yes" || "yup" || "yeah" || "positive";
if answer == ("yes", "yup", "yeah", "positive")
if answer == ["yes" or "yup" or "yeah" or "positive"]
I receive an error which I couldn't solve
answer = gets.chomp
if answer == "yes" or "yup" or "yeah" or "positive"
puts "Good!"
puts desc_text
my_var = gets.chomp.to_i
if my_var == 3736
puts good_text
else
puts wrong_text
puts bad_text
end
elsif answer == [ "no" || "nop" || "nay || ""negative" ]
puts bad_text
else
puts yes_no
end
I'd like to pass different answer options such as yes, yup, yeah, positive instead of just enclose me to a yes and/or no answer
A more idiomatic Ruby way of allowing for these different user options would be to have all possible valid user input stored in an array, then checking if the user provided a valid option by calling include? on the array. This way, you can update the array with more possible options at a later time. Generally arrays like this are stored as constants, though you can also store them as local variables. I find that for a script like this, variables are fine, but if I'm writing a larger program and I need arrays like this (for example, arrays that specify valid options) in a class, then I use constants to make it easy for other contributors to find them. Another option yet would be to have a configuration file (can be a Ruby file, yaml file, JSON file...) that defines valid options, and then you can load this file when executing your program.
Here is an example of what I mean:
VALID_AFFIRMATIVE_ANSWERS = %w(yes yup yea positive)
VALID_NEGATIVE_ANSWERS = %w(no not nay negative)
answer = gets.chomp
if VALID_AFFIRMATIVE_ANSWERS.include?(answer)
puts "Good!"
puts desc_text
my_var = gets.chomp.to_i
if my_var == 3736
puts good_text
else
puts wrong_text
puts bad_text
end
elsif VALID_NEGATIVE_ANSWERS.include?(answer)
puts bad_text
else
puts yes_no
end
I'm not sure what errors you're receiving, but I'm not sure if you're ever defining some of these variables (for example desc_text etc.).
if code is excetly as you write above your issue is in line written below
elsif answer == [ "no" || "nop" || "nay || ""negative" ]
although it won't work , so the solution for you would be like below
def process_positive_response
my_var = gets.chomp.to_i
if my_var == 3736
puts good_text
else
puts wrong_text
puts bad_text
end
end
answer = gets.chomp
case answer
when 'yes','yup','yeah','positive'
puts "Good!"
puts desc_text
process_positive_response
when 'no', 'nop', 'nay', 'negative'
puts bad_text
else
puts yes_no
end
first why write so much conditions when ruby already does that for you with case statement, and second distribute your code in chunks so it will make your code more traceable.
The task is taken from "Learn to Program" by Chrise Pine. The program is called 'Deaf Grandma'. Here's the task: "whatever you type, grandma (the program) should respond with this:
`HUH?! SPEAK UP, SONNY!`
unless you shout it (type in all capitals). In this case she responds with:
`NO, NOT SINCE 1938!`
Have Grandma shout a different year each time, maybe any year at random between 1930 and 1950. You have to shout BYE three times in a row. Make sure to test your program: if you shout
BYE three times but not in a row, you should still be talking to
Grandma."
Now, everything looks fine to me, except I didn't get where to put gets.chomp 3 times to exit a program. Eventually, I came up with this:
speak = gets.chomp
while speak != 'BYE'
puts 'HUH?! SPEAK UP, SONNY!'
if speak == speak.upcase
puts 'NO, NOT SINCE ' + (1930 + rand(20)).to_s + '!'
else repeat = gets.chomp
end
end
But in this case if I type BYE grandma still asks me:
`HUH?! SPEAK UP, SONNY!`
My question is: how can I properly make the program exit after I type BYE three times in a row?
Have a look at this, I've made some changes though. But should give you the expected output.
bye_count = 0
while true
speak = gets.chomp
if speak == 'BYE'
bye_count +=1
bye_count == 3 ? break : next
end
bye_count = 0 # Resets count
if speak == speak.upcase
puts 'NO, NOT SINCE ' + (1930 + rand(20)).to_s + '!'
else
puts 'HUH?! SPEAK UP, SONNY!'
end
end
You've not added anywhere in your code that using 'bye' 3 times will exit the program.
while bye < 3
Try looking at your code again and implementing the changes to exit after 3 byes.
Here's another way:
responses = ["", "", ""]
loop do
speak = gets.chomp
responses.shift
responses << speak
break if responses.all? { |r| r == "BYE" }
if speak == speak.upcase
puts 'NO, NOT SINCE ' + (1930 + rand(20)).to_s + '!'
else
puts 'HUH?! SPEAK UP, SONNY!'
end
end
Alternatively,
break if responses.uniq == ["BYE"]
puts "what can i do for your son?"
a=0
while a != 3
n= gets.chomp
if n.include? 'BYE'
puts "NO NOT SINCE #{rand(1897..1930)}".chomp
a = (a + 1)
end
if n != n.upcase
puts 'HUH?! SPEAK UP, SONNY!'.chomp
a=0
end
if n == n.upcase and n != 'BYE'
puts "NO NOT SINCE #{rand(1897..1930)}".chomp
a=0
end
end
I want to rewrite the following code with the code below, but I am stuck.
def ask question
good_answer = false
while (not good_answer)
puts question
reply = gets.chomp.downcase
if (reply == 'yes' or reply =='no')
good_answer = true
if reply == 'yes'
answer = true
else
answer = false
end
else
puts 'Please answer "yes" or "no"'
end
end
answer
end
Replacement code:
def ask question
puts question
reply = gets.chomp
if (reply == 'yes' or reply == 'no')
puts reply.capitalize
else
puts 'Please enter "yes" or "no"'
#jump the code to like 2 ( but how?)- use while reply != empty & comment the below lines
puts question
reply = gets.chomp
end
end
I want to jump to the main part of program is there any goto, jump or can I call method inside that method?
I want to jump to the main part of program is there any goto, jump or can I call method inside that method?
Yes, it is called a loop, i.e., what you are using in your original code. Why in the world would you want to replace a loop with a goto? Makes no sense.
It can however be simplified. I don't like the checking against 'yes' or 'no', but I also don't have time to restructure your program.
def ask question
while true
puts(question)
reply = gets.chomp.downcase
if reply == 'yes' || reply == 'no'
return reply == 'yes'
else
puts('Please answer "yes" or "no"')
end
end
end
Even if there was a goto statement you shouldn't be using it. Not only is it bad form, but it causes all kinds of headaches for maintainers since your program ends up being hard to follow.
A better approach is to define proper structures for your questions and valid answers, then iterate over those simply, collecting the results into a structure you can use later:
# Auto-flush output buffer
STDOUT.sync = true
questions = [
[ 'Is this a good question?', 'yes', 'no' ],
[ 'Is the sky blue?', 'yes', 'no' ],
[ 'Do hamsters fly?', 'no', 'yes' ]
]
answers_given = [ ]
questions.each do |question, *answers|
print question + ' '
while (true)
answer = gets
answer.chomp!
if (answers.include?(answer))
puts "Thanks!"
answers_given << (answer == answers.first)
break
end
puts "You must answer one of #{answers.join(', ')}!"
print question + ' '
end
end
questions.each_with_index do |(question, *answers), i|
puts "#{question} #{answers_given[i]}"
end
You can try something liek this:
def ask_question
puts('Please answer "yes" or "no"') until (reply = gets.chomp.downcase) =~ /^(yes|no)$/
return reply == 'yes'
end
def ask question
puts question
reply = gets.chomp.downcase
if (reply == 'yes' or reply == 'no')
puts reply.capitalize
else
puts 'Please enter "yes" or "no"'
ask question # this does the looping of loop
end
end
Thanks, and sorry I didn't copy it well from my clipboard last time.