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-- Copyright 2011 by Jannis Pohlmann
-- Copyright 2012 by Till Tantau
--
-- This file may be distributed an/or modified
--
-- 1. under the LaTeX Project Public License and/or
-- 2. under the GNU Public License
--
-- See the file doc/generic/pgf/licenses/LICENSE for more information
-- @release $Header$
--- A Stack is a very simple wrapper around an array
--
--
local Stack = {}
Stack.__index = Stack
-- Namespace
require("pgf.gd.lib").Stack = Stack
--- Create a new stack
function Stack.new()
local stack = {}
setmetatable(stack, Stack)
return stack
end
--- Push an element on top of the stack
function Stack:push(data)
self[#self+1] = data
end
--- Inspect (but not pop) the top element of a stack
function Stack:peek()
return self[#self]
end
--- Pop an element from the top of the stack
function Stack:pop()
return table.remove(self, #self)
end
--- Get the height of the stack
function Stack:getSize()
return #self
end
-- done
return Stack
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