keyword return and consume do not play along well

[kikofernandez]

Given a linear reference:

• if I return the linear reference without consuming it, the typechecker complains
• if I return the linear reference and consume it, the typechecker complains
• if I just consume the reference and have it as the last expression in the method, everything is good

The following example shows these cases:

linear class B
  var x: String = "hola"
end

active class Main
  def test(): B
    new B
  end

  def main(): B
    var b = this.test()
    -- return b  --complains
    -- return consume b -- complains
    consume b -- OK
  end
end

[kikofernandez]

The following test does not work either:

linear class B
  var x: String = "hola"
end

active class Main
  def main(): Maybe[B]
    return Nothing
  end
end

[kikofernandez]

the error message in the second example is:

"test.enc" (line 7, column 5)
Cannot capture expression 'return(Nothing)' of linear type 'Maybe[B]'
In expression: 
  return(Nothing)
In method 'main' of type 'Maybe[B]'
In class 'Main'