Class: OptionList

Inherits:
Object
  • Object
show all
Defined in:
lib/option_list.rb,
lib/option_list/version.rb

Overview

The file option_list.rb and the class OptionList.

This file contains the code for the OptionList class that implements smart and easy options for functions. It has the virtue of defining function options clearly in a single place instead of spread out in complex code.

User’s Guide

Most of the documentation for this gem has been moved to Option List User’s Guide

Version 1.1.1

Embraced reek and git and created the user’s guide to pair down rdoc mark up to be less obtrusive to the code.

Version 1.1.0

Added a default value of false to signify that no default exists for a mandatory parameter. Modified processing of array specs to avoid side effects in the parameters.

Constant Summary collapse

VERSION = 
'1.1.5'

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(*option_specs, &select_block) ⇒ OptionList

Create an option list from an array of option specifications.

Parameters:

  • option_specs - The comma separated option specifications, made into an

array by the splat operator.

  • select_block - An optional block of code that is called when selections

have been made. This allows for custom validations to be applied at that
point. This block should accept one argument, a reference to the option
list value object that is calling it for validation.

Exceptions:

  • ArgumentError for a number of invalid argument conditions.



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# File 'lib/option_list.rb', line 39

def initialize(*option_specs, &select_block)
  error "Missing option specifications." if option_specs.empty?
  @mandatory  = Array.new
  @categories = Hash.new
  @default    = Hash.new

  option_specs.each do |spec|
    if spec.is_a?(Hash)
      hash_spec(spec)
    elsif spec.is_a?(Array)
      array_spec(spec)
    else
      error "Found #{spec.class} instead of Hash or Array."
    end
  end

  @select_block = select_block
end

Class Method Details

.version ⇒ Object

The option list code version.



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# File 'lib/option_list.rb', line 20

def self.version
  OptionList::VERSION
end

Instance Method Details

#select(selections = []) ⇒ Object

From the possible options, select the actual, in force, options and return an access object for use in the code.

Parameters:

  • selections - An array of the options passed into the client function, usually

with the splat operator. Note that if select is called with no arguments,
all of the default values will be selected.

Returns:

An option value object which is a singleton subclass of the Hash class.

Exceptions:

  • ArgumentError for a number of invalid argument conditions.

Notes:

After processing the selections, the selection validation block is called if one was defined for the constructor.



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# File 'lib/option_list.rb', line 71

def select(selections=[])
  selections = [selections] unless selections.is_a?(Array)
  selected = process_selections(selections)

  @mandatory.each do |cat|
    error "Missing mandatory setting #{cat}" unless selected[cat]
  end

  @select_block.call(selected) if @select_block
  selected
end

#version ⇒ Object

The option list code version. This is a redirect to the class method.



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# File 'lib/option_list.rb', line 25

def version
  OptionList::VERSION
end