What favorable naming convention for methods or properties returns a boolean value in Ruby?

Question

I saw it all:

• is_valid

• is_valid?

• valid?

Is there a preferred option?

EDIT: Additional Terms:

• has_comment has_comment? comment?

• was_full was_full? full?

Please add more detailed examples.

Answer 1

I think the convention is basically to add '?' at the end of the method instead of 'is'

• valid?

Answer 2

In favor of a code attempt to be a "natural language" like is_valid? should be the most suitable for me. Let's show an example:

if @ order.is_valid? @ order.save end