Ruby Argument error in convert function - ruby-on-rails

Question

I am trying to run a program from a book that I am learning ruby from, but I keep getting this error no matter how I try to fix it
ex41.rb:70:in `convert': wrong number of arguments (0 for 2) (ArgumentError)
from ex41.rb:117:in `block (2 levels) in <main>'
from ex41.rb:113:in `each'
from ex41.rb:113:in `block in <main>'
from ex41.rb:108:in `loop'
from ex41.rb:108:in `<main>'
I do understand that I have the wrong number of arguments, but the thing is I can't find where I'm getting them wrong, could someone please explain this to me? For convienience I put (LINE XXX(as a number)) by the lines that cause me trouble. Thank you.
# calls external file from web
require 'open-uri'
# assigns WORD_URL to website
WORD_URL = "http://learncodethehardway.org/words.txt"
# creates empty array WORDS
WORDS =[]
# creates hash PHRASES
PHRASES = {
"class ### < ### \nend" =>
"Make a class named ### that is-a ###.",
# my assumption is that ### ### and the like will sb in words, lets find
out
"class ###\n\tdef initialize(###)\n\tend\nend" =>
"class ### has-a initialize that takes ### parameters.",
"class ###\n\tdef ***(###)\n\tend\nend" =>
"class ### has-a function named *** that takes ### parameters.",
"*** = ###.new()" =>
"Set *** to an instance of class ###.",
"***.***(###)" =>
"From *** get the *** function, and call it with parameters ###",
"***.*** = '***'" =>
"From ***, get the *** attribute and set it equal to '***'."
}
# creates variable for first argument if argument is english
PHRASE_FIRST = ARGV[0] == "english"
# opens WORD_URL function and creates function f
open(WORD_URL) {|f|
# for every line in f chomps break character and pushes out word to f
f.each_line {|word| WORDS.push(word.chomp)}
}
# defines function craft_names with variables rand_words, snippet and
pattern, and assigns caps value to false
def craft_names(rand_words, snippet, pattern, caps=false)
# assigns vriable names to snippet.scan on pattern maps and does the
following
function
names = snippet.scan(pattern).map do
# assigns word to rand_words that have popped off the end
word = rand_words.pop()
# Guessing again, maybe capitalizes the first word
caps ? word.capitalize : word
# ends do
end
# returns names twice
return names * 2
# ends craft_names function
end
# defines function craft_params with variables rand_words snippet, and
pattern
def craft_params(rand_words, snippet, pattern)
# assigns names to action scan with variable pattern with action
# length on beginning part of array to snippet and runs the following
# function using map
names = (0...snippet.scan(pattern).length).map do
# assigns variable param_count to an action that takes a random 3 and adds one to it
param_count = rand(3) + 1
# assigns variable params to one long ass action that maps 0 to param_count
value and pops out the last word
params = (0...param_count).map { |x| rand_words.pop() }
# joins params list, (I'm sure its a list) with string ,
params.join(", ")
# ends names for loop
end
# returns names twice
return names * 2
# ends craft_params function
end
# defines convert function with variables snippet and phrase
(LINE 70) def convert(snippet, phrase)
# sords words randomly and assigns words to rand_words
rand_words = WORDS.sort_by {rand}
# assigns class names to function craft mnames on rand_words, snippet /###/, and caps=true
class_names = craft_names(rand_words, snippet, /###/, caps=true)
# assigns other_names to craft_names with variables rand_words, snippet, and /\*\*\*/
other_names = craft_names(rand_words, snippet, /\*\*\*/)
# assigns param_names to craft_params with rand_words, snippet, and ### as variables
param_names = craft_params(rand_words, snippet, /###/)
# assigns empty array results
results = []
# on all variables snippet and phrase matchups perform the function
sentence
[snippet, phrase].each do |sentence|
# fake class names, also copies sentence
result = sentence.gsub(/###/) {|x| param_names.pop}
# fake other names
result.gsub!(/\*\*\*/)
# fake parameter lists
result.gsub!(/###/)
# returns result
results.push(result)
# ends function
end
# returns results
return results
# ends convert function
end
# keep going until they hit ctrl-d
# continual loop
(LINE 108)loop do
# assigns variable snippets to Prases.keys and sorts randomly
snippets = PHRASES.keys().sort_by {rand}
# for snippet in snippets
(LINE113) snippets.each do |snippet|
# assigns PHRASES on snippet to phrase
phrase = PHRASES[snippet]
# asssigns question and answer to converted snippet and phrase
#respectively
(LINE117)question, answer = convert[snippet, phrase]
# if values in phrase firs are equal to answer, question
if PHRASE_FIRST
# question, answer = answer, question
question, answer = answer, question
# ends if
end
# prints question, two line breaks, and > without line break
print question, "\n\n> "
# closes program unless input
exit(0) unless $stdin.gets
# prints line break ANSWER: answer line break line break
puts "\nANSWER: %s\n\n"
# ends unless
end
# ends loop
end

Answer 1

TL;DR – Use convert(snippet, phrase) instead of convert[snippet, phrase]
When you write
convert[snippet, phrase]
... it is equivalent to:
convert()[snippet, phrase]
Adding a space:
convert [snippet, phrase]
... would call the method with an array:
convert([snippet, phrase])
To actually call the method with two arguments, use:
convert(snippet, phrase)
or
convert snippet, phrase