How to check if a string is blank in Elixir

There is String.strip/1 which will convert your 3 examples to "" which you can compare against.

iex(4)> String.strip("\n") == ""
true
iex(5)> String.strip("") == ""  
true
iex(6)> String.strip("    ") == ""
true

There was an issue about it https://github.com/elixir-lang/elixir/pull/2707

String.trim/1 seems to do the trick as of Elixir 1.3.0.

strip still works, but it was soft deprecated in the 1.3.0 release and it isn't listed in the String docs.

I published a tiny library to do this properly for any data type. It implements identical behaviour as Rails' blank? method in Elixir as far as that's possible.

Library is here: https://github.com/samphilipd/blankable

To install, add blankable to your list of dependencies in mix.exs:

def deps do
  [{:blankable, "~> 0.0.1"}]
end