モジュール:TableExtensions

このモジュールについての説明文ページを モジュール:TableExtensions/doc に作成できます

function table.isEmpty(tbl)
	return not next(tbl)
end

function table.keys(tbl)
	local keyset = {}
	for key, _ in pairs(tbl) do
		keyset[#keyset + 1] = key
	end
	return keyset
end

function table.values(tbl)
	local valueset = {}
	for _, value in pairs(tbl) do
		valueset[#valueset + 1] = value
	end
	return valueset
end

function table.entries(tbl)
	local entryset = {}
	for key, value in pairs(tbl) do
		entryset[#entryset + 1] = { key, value }
	end
	return entryset
end

function table.map(tbl, fn)
	local ret = {}
	for key, value in pairs(tbl) do
		ret[key] = fn(key, value)
	end
	return ret
end

function table.mapKeys(tbl, fn)
	local ret = {}
	for key, value in pairs(tbl) do
		ret[fn(key)] = value
	end
	return ret
end

function table.mapValues(tbl, fn)
	local ret = {}
	for key, value in pairs(tbl) do
		ret[key] = fn(value)
	end
	return ret
end

function table.filter(tbl, fn)
	local ret = {}
	for idx, value in ipairs(tbl) do
		if fn(idx, value) then
			ret[#ret + 1] = value
		end
	end
	for key, value in pairs(tbl) do
		if type(key) ~= 'number' and fn(key, value) then
			ret[key] = value
		end
	end
	return ret
end

function table.removeKey(tbl, key)
	local element = tbl[key]
	tbl[key] = nil
	return element
end

function table.reverse(tbl)
	local n = #tbl
	local i = 1
	while i < n do
		tbl[i], tbl[n] = tbl[n], tbl[i]
		i = i + 1
		n = n - 1
	end
end

function table.reversed(tbl)
	local ret = {}
	for i = #tbl, 1, -1 do
		ret[#ret + 1] = tbl[i]
	end
	return ret
end

return table