Rails: What does this shorthand '.map(&:downcase)' mean?

Question

I found this code in codeschool

self.keywords = [title, author, description].map(&:downcase).join(' ')

I know the result that can convert string to downcase, but What does this shorthand (&:downcase) mean?

yes it seems the same, I am just confused about the usage in array. — rj487, Aug 20 '15 at 05:50

score 3 · Accepted Answer · answered Aug 20 '15 at 05:45

3

It is the same as:

self.keywords = [title, author, description].map { |keyword| keyword.downcase }.join(' ')

answered Aug 20 '15 at 05:45

Brad Werth

Thank, quick answer. Great help. – rj487 Aug 20 '15 at 05:48
@CodaChang more info tha you will ever need - http://eli.thegreenplace.net/2006/04/18/understanding-ruby-blocks-procs-and-methods/ – Brad Werth Aug 20 '15 at 05:51

1 Answers1