Question

Is there any way to embed a block inside a string in a way that is executable like this?

for i in 1..1000
  test "There once was #{if i=1{'a man'} else {'many men'} end} from kilkenny"
end

Answer 1

Yes, everything inside of #{} will be evaluated before the string is used, and therefore has to be valid Ruby code. Try:

1.upto(1000) do |i|
  puts "There once was #{i==1?"a man":"many men"} from kilkenny"
end

Here, I’ve used the ternary operator, used in Ruby and other languages, which is basically:

(boolean condition) ? (return this on true) : (return this on false)

Also note the double equal ==, which is the equality operator in Ruby. Single equal, = is the assignment operator, which in your code resets the value of i to 1 in every loop.

Because all values except nil and false are truthy in Ruby, your proposed if .. then will always be true, because i=1 returns 1, which is true.