class Puppet::Functions::InternalFunction

@note WARNING: This style of creating functions is not public. It is a system

under development that will be used for creating "system" functions.

This is a private, internal, system for creating functions. It supports everything that the public function definition system supports as well as a few extra features.

Injection Support

The Function API supports injection of data and services. It is possible to make injection that takes effect when the function is loaded (for services and runtime configuration that does not change depending on how/from where in what context the function is called. It is also possible to inject and weave argument values into a call.

Injection of attributes

Injection of attributes is performed by one of the methods `::attr_injected`, and `::attr_injected_producer`. The injected attributes are available via accessor method calls.

@example using injected attributes

Puppet::Functions.create_function('test') do
  attr_injected String, :larger, 'message_larger'
  attr_injected String, :smaller, 'message_smaller'
  def test(a, b)
    a > b ? larger() : smaller()
  end
end

@api private

Public Instance Methods

call_function_with_scope(scope, function_name, *args) click to toggle source

Allows the implementation of a function to call other functions by name and pass the caller scope. The callable functions are those visible to the same loader that loaded this function (the calling function).

@param scope [Puppet::Parser::Scope] The caller scope @param function_name [String] The name of the function @param *args [Object] splat of arguments @return [Object] The result returned by the called function

@api public

# File lib/puppet/functions.rb, line 546
def call_function_with_scope(scope, function_name, *args)
  internal_call_function(scope, function_name, args)
end

Public Class Methods

attr_injected(type, attribute_name, injection_name = nil) click to toggle source

Defines class level injected attribute with reader method

@api private

# File lib/puppet/functions.rb, line 511
def self.attr_injected(type, attribute_name, injection_name = nil)
  define_method(attribute_name) do
    ivar = :"@#{attribute_name.to_s}"
    unless instance_variable_defined?(ivar)
      injector = Puppet.lookup(:injector)
      instance_variable_set(ivar, injector.lookup(closure_scope, type, injection_name))
    end
    instance_variable_get(ivar)
  end
end

attr_injected_producer(type, attribute_name, injection_name = nil) click to toggle source

Defines class level injected producer attribute with reader method

@api private

# File lib/puppet/functions.rb, line 525
def self.attr_injected_producer(type, attribute_name, injection_name = nil)
  define_method(attribute_name) do
    ivar = :"@#{attribute_name.to_s}"
    unless instance_variable_defined?(ivar)
      injector = Puppet.lookup(:injector)
      instance_variable_set(ivar, injector.lookup_producer(closure_scope, type, injection_name))
    end
    instance_variable_get(ivar)
  end
end

builder() click to toggle source

@api private

# File lib/puppet/functions.rb, line 502
def self.builder
  @type_parser ||= Puppet::Pops::Types::TypeParser.new
  @all_callables ||= Puppet::Pops::Types::TypeFactory.all_callables
  InternalDispatchBuilder.new(dispatcher, @type_parser, @all_callables)
end