CODEWITHSUNDEEP
ruby-on-railsrubyregex
NJ.
NJ.

Reputation: 2175

Simple regex problem in Rails

Ok. It's late and I'm tired.

I want to match a character in a string. Specifically, the appearance of 'a'. As in "one and a half".

If I have a string which is all lowercase.

"one and a half is always good" # what a dumb example. No idea how I thought of that.

and I call titleize on it

"one and a half is always good".titleize #=> "One And A Half Is Always Good"

This is wrong because the 'And' and the 'A' should be lowercase. Obviously.

So, I can do

"One and a Half Is always Good".titleize.tr('And', 'and') #=> "One and a Half Is always Good"

My question: how do I make the "A" an "a" and without making the "Always" into "always"?

Upvotes: 0

Views: 209

Answers (2)

Dogweather
Dogweather

Reputation: 16779

I like Greg's two-liner (first titleize, then use a regex to downcase selected words.) FWIW, here's a function I use in my projects. Well tested, although much more verbose. You'll note that I'm overriding titleize in ActiveSupport:

class String
  #
  # A better titleize that creates a usable
  # title according to English grammar rules.
  #
  def titleize
    count  = 0
    result = []

    for w in self.downcase.split
      count += 1
      if count == 1
        # Always capitalize the first word.
        result << w.capitalize
      else
        unless ['a','an','and','by','for','in','is','of','not','on','or','over','the','to','under'].include? w
          result << w.capitalize
        else
          result << w
        end
      end
    end

    return result.join(' ')
  end
end

Upvotes: 2

the Tin Man
the Tin Man

Reputation: 160551

This does it:

require 'active_support/all'
str = "one and a half is always good" #=> "one and a half is always good"

str.titleize.gsub(%r{\b(A|And|Is)\b}i){ |w| w.downcase } #=> "One and a Half is Always Good"

or

str.titleize.gsub(%r{\b(A(nd)?|Is)\b}i){ |w| w.downcase } #=> "One and a Half is Always Good"

Take your pick of either of the last two lines. The regex pattern could be created elsewhere and passed in as a variable, for maintenance or code cleanliness.

Upvotes: 2

Related Questions