class Arel::Visitors::Visitor

Public Class Methods

new() click to toggle source
# File lib/arel/visitors/visitor.rb, line 4
def initialize
  @dispatch = get_dispatch_cache
end

Private Class Methods

dispatch_cache() click to toggle source
# File lib/arel/visitors/visitor.rb, line 14
def self.dispatch_cache
  Hash.new do |hash, klass|
    hash[klass] = "visit_#{(klass.name || '').gsub('::', '_')}"
  end
end

Public Instance Methods

accept(object) click to toggle source
# File lib/arel/visitors/visitor.rb, line 8
def accept object
  visit object
end

Private Instance Methods

dispatch() click to toggle source
# File lib/arel/visitors/visitor.rb, line 24
def dispatch
  @dispatch
end
get_dispatch_cache() click to toggle source
# File lib/arel/visitors/visitor.rb, line 20
def get_dispatch_cache
  self.class.dispatch_cache
end
visit(object) click to toggle source
# File lib/arel/visitors/visitor.rb, line 28
def visit object
  send dispatch[object.class], object
rescue NoMethodError => e
  raise e if respond_to?(dispatch[object.class], true)
  superklass = object.class.ancestors.find { |klass|
    respond_to?(dispatch[klass], true)
  }
  raise(TypeError, "Cannot visit #{object.class}") unless superklass
  dispatch[object.class] = dispatch[superklass]
  retry
end