Caesars - v0.7¶ ↑

A simple class for rapid DSL prototyping in Ruby.

NOTE: Post-processing of Caesars::Config subclasses changed in 0.7. In 0.6 and earlier, the post-processing hook (Caesars::Config#postprocess) was called after every file was loaded. In 0.7 it’s called after all files have been loaded. This could break some highly dependent code in your subclasses of Caesars::Config so I apologize but I believe this is the right thing to do. If you are not satisfied with that apology, prepare yourself a caesar or bloody mary or any other beverage and send email me with the details!

One of:

• gem install caesars

• copy lib/caesars.rb into your lib directory.

Or for GitHub fans:

• gem install delano-caesars –source gems.github.com

• git clone git://github.com/delano/caesar.git

require 'caesars'

class Flavour < Caesars  # Subclass Caesars.
end

extend Flavour::DSL     # Bring the DSL into the current namespace.
                        # This module is created dynamically based
                        # on the name of the subclass.

flavour do              # Start drinking! I mean, start writing your
  spicy true            # domain specific language!
  clamy true            # Use any attribute name you want.
  salty true
  vodka :very_true      # And any value you want.
end

p @flavour              # => #<Flavour:0x3f56b0 ...>
p @flavour.spicy        # => true

require 'caesars'

class Staff < Caesars

  chill :calculate      # Delay execution of the blocks for the calculate
                        # attribute. They will be stored as Procs.
end

extend Staff::DSL

# The top level method is the lower case name of the class. For deeper
# names like Class::SecondLevel it will use the final name
# (i.e. secondlevel). You can supply an optional modifier name which
# will be included in the instance variable (@staff_fte).
staff :fte do
  desc 'Our hard-working, "full-time" staff'

  location :splashdown do
    town :tsawwassen

    person :steve, :sheila do
      role :manager
    end

    person :steve do
      role :cook
      anger :high
      hours 25
      catchphrase "Rah! [strokes goatee]"
    end

    person :sheila do
      catchphrase "This gravy tastes like food I ate in a Mexican prison."
      hours rand(20)
      rate "9.35/h"
      calculate :salary do |gumption|
        ("%.2f" % [gumption * self.splashdown.sheila.rate.to_f]).to_f
      end
    end

    person :delano do
      role :cook
      rate "8.35/h"
      hours 57
      satisfaction :low
      calculate :salary do 
        self.splashdown.delano.rate.to_f * self.splashdown.delano.hours
      end
    end

  end
end

p @staff_fte                    # => #<Staff: ...>
p @staff_fte.desc               # => Our hard-working, "full-time" staff

# Deeper attributes are also available via instance methods
p @staff_fte.splashdown.delano  # => {:role=>:cook, :rate=>"$8.35/h", :satisfaction=>:low}
p @staff_fte.splashdown.sheila  # => {:role=>:manager, :catchphrase=>"This gravy tastes like food I ate in a Mexican prison."}
p @staff_fte.splashdown.steve   # => {:role=>[:manager, :cook], :anger=>:high, :catchphrase=>"Rah! [strokes goatee]"}
p @staff_fte.splashdown.delano.satisfaction   # => :low

# You can also access them using hash syntax
p @staff_fte.splashdown[:steve][:role]  # => [:manager, :cook]

# The "chilled" attributes store their blocks as Procs and are not executed automatically.
# You can call them manually and send arguments like you normally would.
p @staff_fte.splashdown.delano.salary.call             # => 475.95
p @staff_fte.splashdown.sheila.salary.call(rand(100))  # => 549.77

require 'caesars'

class Food < Caesars
  chill :order
end
class Drink < Caesars
end

class PartyConfig < Caesars::Config
  dsl Food::DSL
  dsl Drink::DSL
end

conffile = File.join(File.dirname(__FILE__), 'party.conf')
@config = PartyConfig.new(conffile)

p @config.food.order.call   # => 10kg
p @config[:drink][:wine]    # => 12L
p @config                   # => <PartyConfig:0x3f780c ...>
p @config.keys              # => [:food, :drink]

# [... make changes to party.conf ...]

@config.refresh

party.conf

food do 
  oysters "10kg"
  order do
    self.oysters
  end
end

drink do
  wine "12L"
end

• GitHub

• Inspiration

• Recipe

• OrderedHash implementation by jan molic

• Delano Mandelbaum (delano@solutious.com)

• Clams, Tomatoes, Grey Goose, and the rest of the crew.

• Caleb Buxton (cpb.ca) for early feedback.

• Solutious Inc (solutious.com)

• DSLify

See: LICENSE.txt