: Alias::Creator [RDoc Documentation]

This is the base creator class. To be a valid subclass, the creator must define Alias::Creator.map and Alias::Creator.generate. Although not required, creators should enforce validation of their aliases with Alias::Creator.valid. Also, the creator should be named in the format Alias::Creators::*Creator where the asterisk stands for any unique string. Since that string is converted to an underscored version when referenced in the console, it’s recommended to make it camel case. For example, Alias::Creators::InstanceMethodCreator is referenced by it’s underscored version :instance_method.

To better understand how a creator works, here’s the steps a creator goes through when creating aliases:

map() : Maps the hash from a config file or console input into an array of alias hashes.
valid() : Defines a validation that each alias hash must pass.
generate() : Given the array of alias hashes, generates the string of ruby code to be evaled for alias creation.

Methods

public instance

create
delete_invalid_aliases

Classes and Modules

Class Alias::Creator::AbstractMethodError
Class Alias::Creator::FailedAliasCreationError

Attributes

aliases	[RW]	Array of alias hashes that have been created.
force	[RW]	Same purpose as Alias::Manager.verbose and Alias::Manager.force but unlike them these only take a boolean.
verbose	[RW]	Same purpose as Alias::Manager.verbose and Alias::Manager.force but unlike them these only take a boolean.

Public class methods

creators ()

Array of all Creator subclasses.

[show source]

# File lib/alias/creator.rb, line 75
      def creators; @creators; end

generate (&block)

Takes a block which converts aliases to a string of ruby code to run through Kernel#eval.

[show source]

# File lib/alias/creator.rb, line 61
      def generate(&block)
        @generate = block
      end

map (&block)

Takes a block which converts the creator’s config to an array of aliases.

[show source]

# File lib/alias/creator.rb, line 52
      def map(&block)
        @map = block
      end

valid (key, options={})

Creates a validation expectation for the creator by giving it an Alias::Validator object aka validator. This method must be given an :if or :unless option. If the :if option returns false or :unless option returns true for an alias, the alias is skipped.

Options:

:if: Takes a proc or a symbol referencing a registered validator. This proc must evaluate to true for the validation to pass. See Alias::Validator.validate for what arguments this proc receives by default. See Alias::Validator.default_validators for validators that can be referenced by symbol.
:unless: Same as :if option but the result is negated.
:message: A proc to print a message if the creator’s verbose flag is set. Receives same arguments as :if and :unless procs. If a previous validator is referenced in :unless or :if, then their :message is inherited.
:with: An array of alias attributes/keys which specify the current alias attributes to pass to the validator procs. Overrides default argument a validator proc receives.
:optional: When set to true, this option can be overridden in conjunction with a creator’s force flag. Default is false.

[show source]

# File lib/alias/creator.rb, line 31
      def valid(key, options={})
        begin
          validators[key] = Validator.new(options.merge(:key=>key, :creator=>self))
        rescue Validator::MissingConditionError
          raise ArgumentError, "A :unless or :if option is required."
        rescue Validator::InvalidValidatorError
          $stderr.puts "Validator not set for #{key}"
          @validators.delete(key)
        end
      end

Public instance methods

create (aliases_hash, pretend=false)

Main method used to create aliases. Handles mapping, validation and creation of aliases.

[show source]

# File lib/alias/creator.rb, line 90
    def create(aliases_hash, pretend=false)
      aliases_array = self.class.maps_config(aliases_hash)
      delete_invalid_aliases(aliases_array)
      self.aliases = aliases + aliases_array unless pretend
      begin
        #td: create method for efficiently removing constants/methods in any namespace
        eval_string = Util.silence_warnings { self.class.generates_aliases(aliases_array) }
        pretend ? puts("\n", eval_string) : Kernel.eval(eval_string)
      rescue
        raise FailedAliasCreationError, $!
      end
    end

delete_invalid_aliases (arr)

Deletes invalid alias hashes that fail defined validators for a creator.

[show source]

# File lib/alias/creator.rb, line 104
    def delete_invalid_aliases(arr)
      arr.delete_if {|alias_hash|
        !self.class.validators.all? {|attribute, validator|
          validator.validate(self, alias_hash, attribute)
        }
      }
    end