Module:FunList/Enumerable
Implementation of the base Enumerable class. This class and its inheritants map the Lua pairs and ipairs functions to a state machine. Inheritants must implement the getEnumerator function that returns an Module:FunList/Enumerator object.
-- Makes the class that inherits this enumerable with pairs and ipairs
--- @class Enumerable
local Enumerable = {}
local Enumerable_mt = {
__index = Enumerable,
__pairs = Enumerable.getPairs,
__ipairs = Enumerable.getiPairs
}
function Enumerable.new()
local self = setmetatable({}, Enumerable_mt)
return self
end
--- Enumerate all elements
--- @param isArray? boolean
--- @return Enumerator
function Enumerable:getEnumerator(isArray)
error("This method must be implemented by the derived class")
end
---comment
---@param enum Enumerable
---@param startIndex any
local function overridePairs(enum, startIndex)
local new = enum:getEnumerator(startIndex == 0)
local next = new.moveNext
local function iterator(t, k)
if next(new) == true then
return new.index, new.current
end
return nil, nil
end
return iterator, new, new.index
end
function Enumerable:getPairs()
return overridePairs(self, nil)
end
function Enumerable:getiPairs()
return overridePairs(self, 0)
end
--- @param obj any
--- @return boolean
function Enumerable.isEnumerable(obj)
-- Instead of checking type, we just really only care
-- if obj implements the getEnumerator function.
if obj == nil then
return false
end
return (obj.getEnumerator ~= nil)
end
return Enumerable