rubyx/lib/slot_machine/slot.rb
Torsten Rüger c1679bd6ff Makes slots linked list
slots used to ba an array of symbols
Now we have an object for each slot, that holds the name and the next_slot
relatively easy change, though quite broad
2020-02-17 14:29:45 +07:00

51 lines
1.5 KiB
Ruby

module SlotMachine
# A Slot defines a slot in a slotted. A bit like a variable name but for objects.
#
# PS: for the interested: A "development" of Smalltalk was the
# prototype based language (read: JavaScript equivalent)
# called Self https://en.wikipedia.org/wiki/Self_(programming_language)
#
# Slots are the instance names of objects. But since the language is dynamic
# what is it that we can say about instance names at runtime?
# Start with a Slotted, like the Message (in register one), we know all it's
# variables. But there is a Message in there, and for that we know the instances
# too. And off course for _all_ objects we know where the type is.
#
# The definiion is an array of symbols that we can resolve to SlotLoad
# Instructions. Or in the case of constants to ConstantLoad
#
class Slot
attr_reader :name , :next_slot
# initialize with just the name of the slot. Add more to the chain with set_next
def initialize( name )
raise "No name" unless name
@name = name
end
#set the next_slot , but always at the end of the chain
def set_next(slot)
if(@next_slot)
@next_slot.set_next(slot)
else
@next_slot = slot
end
end
# return the length of chain, ie 1 plus however many more next_slots there are
def length
return 1 unless @next_slot
1 + @next_slot.length
end
# name of all the slots, with dot syntax
def to_s
names = name.to_s
names += ".#{@next_slot}" if @next_slot
names
end
end
end