Question

I’m doing the Ruby 20 minute tutorial on ruby-lang.org and I came across this code messing with the irb:

irb(main):015:0> def h(name)
irb(main):016:1> puts "Hello #{name}!"
irb(main):017:1> end

based on the explanation, the #{name} part is just adding the variable to the string? I thought this was an odd and verbose way of writing it so I just thought I’d try "Hello" + name and it worked exactly the same way..

I googled around trying to find a meaning to #{} and I cant find anything talking about it so I thought I’d ask the community.. what is the difference? Is there one?

Thanks in advance!

Answer 1

Sometimes using + is easier, but in this case you left off the exclamation point. Consider:

puts "Hello #{name}!"

vs.

puts "Hello " + name + "!"

I find the first more readable, especially when used several times in a string.

Also consider how easy it was to leave out the space after “Hello” in the second version:

puts "Hello" + name + "!"

is easy to write, but probably isn’t what you mean.

Last, it makes an even bigger difference when what you’re interpolating isn’t a string:

puts "The Winner was #{name} with a score of #{score}!"

By the way, searching for “string interpolation” will probably make it easier to find things than just searching for the syntax.