Created
October 7, 2019 16:57
Circular Linked List
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
macro container_of(ptr, _type, member) | |
{% if _type.resolve < Reference %} | |
(({{ ptr }}).as(Void*) - offsetof({{ _type }}, {{ member }})).as({{ _type }}) | |
{% else %} | |
(({{ ptr }}).as(Void*) - offsetof({{ _type }}, {{ member }})).as(Pointer({{ _type }})) | |
{% end %} | |
end | |
struct StaticList | |
@prev = uninitialized Pointer(StaticList) | |
@next = uninitialized Pointer(StaticList) | |
def prev | |
@prev | |
end | |
def prev=(@prev) | |
end | |
def next | |
@next | |
end | |
def next=(@next) | |
end | |
def self_pointer | |
(->self.itself).closure_data.as(Pointer(StaticList)) | |
end | |
def self.link(prev : StaticList*, _next : StaticList*) | |
prev.value.next = _next | |
_next.value.prev = prev | |
end | |
protected def self.insert_impl(new : StaticList*, prev : StaticList*, _next : StaticList*) | |
link prev, new | |
link new, _next | |
end | |
def init | |
tmp = self_pointer | |
typeof(self).link tmp, tmp | |
end | |
def append_to(list : StaticList*) | |
typeof(self).insert_impl self_pointer, list.value.prev, list | |
end | |
def prepend_to(list : StaticList*) | |
typeof(self).insert_impl self_pointer, list, list.value.next | |
end | |
def remove | |
typeof(self).link @prev, @next | |
end | |
def move_to_front(list : StaticList*) | |
remove | |
prepend_to list | |
end | |
def move_to_back(list : StaticList*) | |
remove | |
append_to list | |
end | |
def empty? | |
@next == self_pointer | |
end | |
def each | |
head = self_pointer | |
it = @next | |
while it != head | |
yield it | |
it = it.value.next | |
end | |
end | |
end | |
class Node | |
@link = StaticList.new | |
def initialize(@x : Int32) | |
end | |
def x | |
@x | |
end | |
def link | |
@link | |
end | |
def link_pointer | |
pointerof(@link) | |
end | |
end | |
list = StaticList.new | |
list.init | |
pp GC.stats | |
10.times do |i| | |
node = Node.new i | |
node.link.append_to(pointerof(list)) | |
end | |
pp GC.stats | |
GC.collect | |
pp GC.stats | |
list.each do |it| | |
node = container_of(it, Node, @link) | |
puts node.x | |
end | |
GC.stats |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment