Ruby: Most concise way to use an ENV variable if it exists, otherwise use default value

Question

In Ruby, I am trying to write a line that uses a variable if it has been set, otherwise default to some value:

myvar = # assign it to ENV[\'MY_VAR\'], otherw         


        

Answer 1

myvar = ENV.fetch('MY_VAR') { 'foobar' }

'foobar' being the default if ENV['MY_VAR'] is unset.