rubyx/lib/parfait/behaviour.rb
Torsten Rüger d901c6f27c rename meta to singleton class
seems more appropriate, as it is the class for a single object
Also seems to be called that on the net (don't remember where the meta came from, but it's gone)
2019-09-23 20:57:33 +03:00

77 lines
2.4 KiB
Ruby

module Parfait
# Behaviour is the old smalltalk name for the duperclass of class and singleton_class
#
# Classes and singleton_classes are in fact very similar, in that they manage
# - the type of instances
# - the methods for instances
#
# The main way they differ is that Classes manage type for a class of objects (ie many)
# whereas singleton_class, or singleton_class manages the type of only one object (here a class)
#
# Singleton classes can manage the type/methods of any single object, and in the
# future off course they will, just not yet. Most single objects don't need that,
# only Classes and Modules _always _ do, so that's where we start.
#
class Behaviour < Object
attr_reader :instance_type , :instance_methods
def initialize(type)
super()
@instance_methods = List.new
@instance_type = type
end
def methods
@instance_methods
end
def method_names
names = List.new
methods.each do |method|
names.push method.name
end
names
end
def add_instance_method_for(name , type , frame , body )
method = Parfait::VoolMethod.new(name , type , frame , body )
add_instance_method( method )
end
def add_instance_method( method )
raise "not implemented #{method.class} #{method.inspect}" unless method.is_a? VoolMethod
@instance_methods.push(method)
method
end
def remove_instance_method( method_name )
found = get_instance_method( method_name )
found ? methods.delete(found) : false
end
def get_instance_method( fname )
raise "get_instance_method #{fname}.#{fname.class}" unless fname.is_a?(Symbol)
#if we had a hash this would be easier. Detect or find would help too
@instance_methods.find {|m| m.name == fname }
end
# get the method and if not found, try superclasses. raise error if not found
def resolve_method( m_name )
raise "resolve_method #{m_name}.#{m_name.class}" unless m_name.is_a?(Symbol)
method = get_instance_method(m_name)
return method if method
if( super_class_name && super_class_name != :Object )
method = @super_class.resolve_method(m_name)
end
method
end
# adding an instance changes the instance_type to include that variable
def add_instance_variable( name , type)
@instance_type = @instance_type.add_instance_variable( name , type )
end
end
end