Ruby String Functions

• “i got what i want”.count “i” #=> 2
• “i got what i want”.delete “i” #=> ” got what want”
• “hello”.gsub(/[aeiou]/, ‘*’) #=> “h*ll*”
• “hello”.sub(/[aeiou]/, ‘*’) #=> “h*llo”
• “hello”.tr(‘aeiou’, ‘*’) #=> “h*ll*”
• “hello”.index(‘e’) #=> 1
• “hello”.rindex(‘l’) #=> 3(last occurrence)
• “abcd”.insert(3, ‘X’) #=> “abcXd”
• ‘cat’.to_sym #=> :cat
• “hello”.ljust(20) #=> “hello “
• “hello”.ljust(20, ’1234′) #=> “hello123412341234123″
• “hello”.rjust(20, ’1234′) #=> “123412341234123hello”
• ” hello “.rstrip #=> ” hello”
• ” hello “.lstrip #=> “hello “
• ” hello “.strip #=> “hello”
• a = “cruel world”
• a.scan(/\w+/) #=> ["cruel", "world"]
• a.scan(/…/) #=> ["cru", "el ", "wor"]
• a.scan(/(…)/) #=> [["cru"], ["el "], ["wor"]]
• a.scan(/(..)(..)/) #=> [["cr", "ue"], ["l ", "wo"]]
• “1,2,,3,4,,”.split(‘,’) #=> ["1", "2", "", "3", "4"]
• “putters shoot balls”.squeeze(“m-z”) #=> “puters shot balls”
• “Finally, something useful!”.at(6) #=> “y”
• “Chris the Person”.from(6) #=> “the Person”
• “Chris the Person”.to(4) #=> “Chris”
• “Christmas Time”.first #=> “C”
• “Christmas Time”.first(5) #=> “Chris”
• “Christmas Time”.last #=> “e”
• “Christmas Time”.last(4) #=> “Time”
• “Snow”.each_char { |i| print i.upcase } #=>SNOW
• “Peanut Butter”.starts_with? ‘Peanut’ #=> true
• “Peanut Butter”.ends_with? ‘Nutter’ #=> false
• “1985-03-13″.to_time #=> Wed Mar 13 00:00:00 UTC 1985
• “1985-03-13″.to_date #=> #
• “stressed”.reverse #=> “desserts”
• “Hello”.swapcase #=> “hELLO”
• “hEllO”.upcase #=> “HELLO”
• “reindeer”.pluralize #=> “reindeers”
• “elves”.singularize #=> “elf”
• “christmas_carol”.camelize #=> “ChristmasCarol”
• “christmas_carol”.camelize(:lower) #=> “christmasCarol”
• “holiday_cheer”.titleize #=> “Holiday Cheer”
• “AdventCalendar-2006″.underscore #=> “advent_calendar_2006″
• “santa_Claus”.dasherize #=> “santa-Claus”
• “Holiday::December::Christmas”.demodulize #=> “Christmas”
• “SnowStorm”.tableize #=> “snow_storms”
• “snow_storms”.classify #=> “SnowStorm”
• “present_id”.humanize #=> “Present”
• “Present”.foreign_key #=> “present_id”
• “Cheer”.constantize #=> NameError: uninitialized constant Cheer
• “Christmas”.constantize #=> Christmas