Sha256: 04b126560e0d9f3de571f1d66d2d3e53eab0495107aaaa6dcdd36d1a18ac3fe3
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Versions: 8
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Contents
require 'active_support/concern'
module Neo
module Rails
# A really simple version of exposing variables to the view.
# Bases on attr_reader and helper_method.
module Exposure
extend ActiveSupport::Concern
class UndeclaredVariableError < StandardError; end
included do
class_attribute :exposed_vars
self.exposed_vars ||= Set.new
end
module ClassMethods
# Defines the variables to be exposed.
def exposes(*names)
exposures = names.map(&:to_sym)
self.exposed_vars.merge exposures
attr_reader *exposures
helper_method *exposures
end
end
# Expose an assign at the instance level.
#
# If the value is given with a block, just execute the block
# if a value was not set yet.
#
# Raise UndeclaredVariableError if access variable wasn't declared before.
def expose(key, value=nil)
name = key.to_sym
raise UndeclaredVariableError unless self.class.exposed_vars.include?(name)
value = yield if block_given?
self.instance_variable_set("@#{name}", value)
end
private
def exposed?(name)
instance_variable_get("@#{name}")
end
end
end
end
Version data entries
8 entries across 8 versions & 1 rubygems