class String

String inflections define new methods on the String class to transform names for different purposes.

def camelize(first_letter = :upper)

"active_record/errors".camelize(:lower) # => "activeRecord::Errors"
"active_record/errors".camelize # => "ActiveRecord::Errors"
"active_record".camelize(:lower) # => "activeRecord"
"active_record".camelize # => "ActiveRecord"

+camelize+ will also convert '/' to '::' which is useful for converting paths to namespaces.

is set to :lower then camelize produces lowerCamelCase.
By default, +camelize+ converts strings to UpperCamelCase. If the argument to camelize 
def camelize(first_letter = :upper)
  case first_letter
    when :upper then Inflector.camelize(self, true)
    when :lower then Inflector.camelize(self, false)
  end
end

def classify

"business".classify # => "Busines"

Singular names are not handled correctly.

"posts".classify # => "Post"
"egg_and_hams".classify # => "EggAndHam"

follow +classify+ with +constantize+.)
Note that this returns a string and not a class. (To convert to an actual class
Create a class name from a plural table name like Rails does for table names to models. 
def classify
  Inflector.classify(self)
end

def dasherize

"puni_puni" # => "puni-puni"

Replaces underscores with dashes in the string. 
def dasherize
  Inflector.dasherize(self)
end

def demodulize

"Inflections".demodulize # => "Inflections"
"ActiveRecord::CoreExtensions::String::Inflections".demodulize # => "Inflections"

Removes the module part from the constant expression in the string. 
def demodulize
  Inflector.demodulize(self)
end

def humanize

"author_id" # => "Author"
"employee_salary" # => "Employee salary"

Like +titleize+, this is meant for creating pretty output.
Capitalizes the first word, turns underscores into spaces, and strips '_id'. 
def humanize
  Inflector.humanize(self)
end

def pluralize

"CamelOctopus".pluralize # => "CamelOctopi"
"the blue mailman".pluralize # => "the blue mailmen"
"words".pluralize # => "words"
"sheep".pluralize # => "sheep"
"octopus".pluralize # => "octopi"
"post".pluralize # => "posts"

Returns the plural form of the word in the string. 
def pluralize
  Inflector.pluralize(self)
end

def singularize

"CamelOctopi".singularize # => "CamelOctopus"
"the blue mailmen".singularize # => "the blue mailman"
"word".singularize # => "word"
"sheep".singularize # => "sheep"
"octopi".singularize # => "octopus"
"posts".singularize # => "post"

The reverse of +pluralize+, returns the singular form of a word in a string. 
def singularize
  Inflector.singularize(self)
end

def titleize

"x-men: the last stand".titleize # => "X Men: The Last Stand"
"man from the boondocks".titleize # => "Man From The Boondocks"

+titleize+ is also aliased as +titlecase+.

used in the Rails internals.
a nicer looking title. +titleize+ is meant for creating pretty output. It is not
Capitalizes all the words and replaces some characters in the string to create 
def titleize
  Inflector.titleize(self)
end

def underscore

"ActiveRecord::Errors".underscore # => active_record/errors
"ActiveRecord".underscore # => "active_record"

+underscore+ will also change '::' to '/' to convert namespaces to paths.

The reverse of +camelize+. Makes an underscored, lowercase form from the expression in the string. 
def underscore
  Inflector.underscore(self)
end