Ruby capitalize every word first letter

try this:

puts 'one TWO three foUR'.split.map(&:capitalize).join(' ')

#=> One Two Three Four

or

puts 'one TWO three foUR'.split.map(&:capitalize)*' '

In Rails:

"kirk douglas".titleize => "Kirk Douglas"
#this also works for 'kirk_douglas'

w/o Rails:

"kirk douglas".split(/ |\_/).map(&:capitalize).join(" ")

#OBJECT IT OUT
def titleize(str)
  str.split(/ |\_/).map(&:capitalize).join(" ")
end

#OR MONKEY PATCH IT
class String  
  def titleize
    self.split(/ |\_/).map(&:capitalize).join(" ")
  end
end

w/o Rails (load rails's ActiveSupport to patch #titleize method to String)

require 'active_support/core_ext'
"kirk douglas".titleize #=> "Kirk Douglas"

(some) string use cases handled by #titleize

  • "kirk douglas"
  • "kirk_douglas"
  • "kirk-douglas"
  • "kirkDouglas"
  • "KirkDouglas"

#titleize gotchas

Rails's titleize will convert things like dashes and underscores into spaces and can produce other unexpected results, especially with case-sensitive situations as pointed out by @JamesMcMahon:

"hEy lOok".titleize #=> "H Ey Lo Ok"

because it is meant to handle camel-cased code like:

"kirkDouglas".titleize #=> "Kirk Douglas"

To deal with this edge case you could clean your string with #downcase first before running #titleize. Of course if you do that you will wipe out any camelCased word separations:

"kirkDouglas".downcase.titleize #=> "Kirkdouglas"

"hello world".titleize which should output "Hello World".

Tags:

String

Ruby

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