This page contains automated test results for code from O'Reilly's Ruby Cookbook. If this code looks interesting or useful, you might want to buy the whole book.

Code Blocks
CodeExpectedActual
[1,2,3].each {|i| puts i}
 
1
2
3
 
1
2
3
 
[1,2,3].each { |i| puts i }
 
1
2
3
 
1
2
3
 
[1,2,3].each do |i|
  if i % 2 == 0
    puts "#{i} is even."
  else
    puts "#{i} is odd."
  end
end
 
1 is odd.
2 is even.
3 is odd.
 
1 is odd.
2 is even.
3 is odd.
 
1.upto 3 do |x|
  puts x
end
 
1
2
3
 
1
2
3
 
1.upto 3 { |x| puts x }
 
SyntaxError: compile error
...
 
SyntaxError: compile error
(irb):13: parse error, unexpected '{', expecting $
1.upto 3 { |x| puts x }
          ^
	from (irb):13

1.upto(3) { |x| puts x }
 
1
2
3
 
1
2
3
 
hello = proc { "Hello" }
hello.call
 "Hello" "Hello" 
log = Proc.new { |str| puts "[LOG] #{str}" }
log.call("A test log message.")
 
[LOG] A test log message.
 
[LOG] A test log message.
 
{1=>2, 2=>4}.each { |k,v| puts "Key #{k}, value #{v}" }
 
Key 1, value 2
Key 2, value 4
 
Key 1, value 2
Key 2, value 4
 
def times_n(n)
  lambda { |x| x * n }
end
times_ten = times_n(10)
times_ten.call(5)
 50 50 
times_ten.call(1.25)
 12.5 12.5 
circumference = times_n(2*Math::PI)
circumference.call(10)
 62.8318530717959 62.8318530717959 
circumference.call(3)
 18.8495559215388 18.8495559215388 
[1, 2, 3].collect(&circumference)
 [6.28318530717959, 12.5663706143592, 18.8495559215388] [6.28318530717959, 12.5663706143592, 18.8495559215388] 
ceiling = 50
 
Which of these numbers are less than the target?
 






[1, 10, 49, 50.1, 200].select { |x| x < ceiling }

[1, 10, 49]
[1, 10, 49]