A little thing about .to_str
Playing with Ruby’s === today and found some knowledge that’s share-worthy. I noticed in ruby docs for “string ===” a reference to “.to_str” and decided to investigate.
Nothing too exciting here, but its an important point of reference.
> hello = "hello" > goodbye = "goodbye" > hello === hello #=> true > hello === goodbye #=> false
This is also what would usually be expected. Hang in there…
> string = "string" > object = Object.new > string + object #=> TypeError no implicit conversion
Here’s where things get funky.
class SomeObjectWithToStr def to_str "is now a string" end end > string = "string" > object = SomeObjectWithToStr.new > string + object #=> "string is now a string" > "string is now a string" === "string" + object #=> true
Hunh? Why did that work?
TIL that .to_str is the default method call when operators force a conversion to a string. You’ll likely have to define it yourself. Also note that the object type on the left is what the object type on the right will try to convert into.
Do you know of any Objects that come with pre-defined .to_str methods?