Ruby -- If Elsif Else Error - ruby

Question

I'm getting an error here with a simple if else chain, and I can't figure out what is going on. I started learning ruby the other day, I already know some java, and was just trying to re-write programs to learn ruby faster. I am trying to tally vowels and consonants. Anyways here is my code...
#!/usr/bin/ruby/
alphabet = 'abcdefghijklmnopqrstuvwxyz'
array = alphabet.chars.to_a
vowel = 0
cons = 0
puts array.at(1)
for i in 0...26
if array.at(i) == "a"
vowel++
elsif array.at(i) == 'e'
vowel++
elsif array.at(i) == 'i'
vowel++
elsif array.at(i) == 'o'
vowel++
elsif array.at(i) == 'u'
vowel++
else
cons++
end#end if else chain
end#end for loop
puts 'Vowel: ' + vowel.to_s
puts 'Consonants: ' + cons.to_s
Here is the error I am getting:
C:/Users/Kelan/Documents/Programming/Ruby
Files/Little Programs/Alphabet.rb:11:
syntax error, unexpected keyword_elsif
elsif array.at(i) == 'e'
^
C:/Users/Kelan/Documents/Programming/Ruby
Files/Little Programs/Alphabet.rb:13:
syntax error, unexpected keyword_elsif
elsif array.at(i) == 'i'
^
C:/Users/Kelan/Documents/Programming/Ruby
Files/Little Programs/Alphabet.rb:15:
syntax error, unexpected keyword_elsif
elsif array.at(i) == 'o'
^
C:/Users/Kelan/Documents/Programming/Ruby
Files/Little Programs/Alphabet.rb:17:
syntax error, unexpected keyword_elsif
elsif array.at(i) == 'u'
^
C:/Users/Kelan/Documents/Programming/Ruby
Files/Little Programs/Alphabet.rb:19:
syntax error, unexpected keyword_else
C:/Users/Kelan/Documents/Programming/Ruby
Files/Little Programs/Alphabet.rb:21:
syntax error, unexpected keyword_end
C:/Users/Kelan/Documents/Programming/Ruby
Files/Little Programs/Alphabet.rb:25:
syntax error, unexpected $end,
expecting keyword_end puts
'Consonants: ' + cons.to_s
^
[Finished in 0.203 seconds]
I'm sure it's just something silly, but I've been looking forever online for help and I have heard of your great community, so I thought I would try here,
Kelan

Answer 1

There is no ++ operator in Ruby. You should have used += 1
You may also want to learn about case statement:
alphabet = 'abcdefghijklmnopqrstuvwxyz'
26.times do |i|
case alphabet[i]
when 'a' then vowel += 1
when 'e' then vowel += 1
when 'i' then vowel += 1
when 'o' then vowel += 1
when 'u' then vowel += 1
else cons += 1
end#end case
end#end times
puts 'Vowel: ' + vowel.to_s
puts 'Consonants: ' + cons.to_s
Or, even better, use method count from class String, like this:
alphabet = 'abcdefghijklmnopqrstuvwxyz'
vowels = 'aeiou'
vowel_count = alphabet.count vowels
cons_count = alphabet.length - vowel_count
puts "Vowels: #{vowel_count}"
puts "Consonants: #{cons_count}"

Answer 2

Your problem is you're using the Java/PHP/C style increment operator. Ruby isn't down with that. You have to use foo += 1 instead.
How about I show you a more Ruby way of doing this though?
# use a range to define your alphabet
alphabet = ('a'..'z').entries #=> ['a', 'b', 'c', ...]
# define vowels as members of an array. it's more flexible, which
# is great for things that change (what if you decide to use 'y'?)
vowels = %w{ a e i o u } #=> ['a', 'e', 'i', 'o', 'u']
# keep counts all together in a hash, which I personally find cleaner
counts = { :vowels => 0, :consonants => 0 }
# even the `for` loops in ruby use the iterators, so you actually
# get better performance out of using the more user-friendly `.each`
alphabet.each do |letter|
if vowels.include? letter
counts[:vowels] += 1
else
counts[:consonants] += 1
end
end
puts "There were #{counts[:vowels]} vowels and #{counts[:consonants]} consonants."

Answer 3

I think rather than vowel++ and con++, you need to use vowel+=1 and con+=1.
Ruby does not have C-style pre/post incrementors.

Answer 4

Here is yet another way to write the demo:
puts("%d vowels & %d consonants" % ('a'..'z').inject([0,0]) do |m, e|
m[/[aeiou]/.match(e) ? 0:1] += 1; m
end)

Answer 5

There is an easy way of constructing the set of alphabets, using Range.
Since you are using ruby, you should use internal iterators instead of the external ones. You will rarely see a for loop in a good program in ruby.
case construction is handy in this case. You can put multiple matching patterns into one, separated by comma.
There is no ++ or -- operators in ruby. Use += 1.
Use "#{ }" notation. It's much better and faster than using +. In fact, you can omit to_s if you use it.
I would go like this:
vowel = 0
cons = 0
('a'..'z').each do |c|
case c
when 'a', 'e', 'i', 'o', 'u'; vowel += 1
else cons += 1
end
end
puts "Vowel: #{vowel}"
puts "Consonants: #{cons}"
If I wanted a shorter one, I might go with this:
partition = ('a'..'z').group_by{|c| c =~ /[aeiou]/}
puts "Vowel: #{partition[0].length}"
puts "Consonants: #{partition[nil].length}"