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Re: Issues with the current varargs implementation (Was: Re: inadequate documentation for select and table.unpack)

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On 16-06-23 02:53 AM, Viacheslav Usov wrote:
> So for n > 9, there is no reason to prefer select over {...}.
For my test case iterating table after table.pack(...) is faster
than direct select()-ing when n >= 7.
--[[
 Tests relative performance between direct select() and
 table.pack() and iterating table for variadic functions.
]]
local op_1 =
 function(...)
 local num_args = select('#', ...)
 for i = 1, num_args do
 local term = select(i, ...)
 end
 end
local op_2 =
 function(...)
 local args = table.pack(...)
 local num_args = args.n
 for i = 1, num_args do
 local term = args[i]
 end
 end
local list_size = 10
local list = {}
for i = 1, list_size do
 list[i] = i
end
local test =
 function(op)
 local result = 0
 local start_time = os.clock()
 local finish_time = start_time + 1
 while (os.clock() <= finish_time) do
 op(table.unpack(list))
 result = result + 1
 end
 return result
 end
print(('Number of arguments: %d'):format(list_size))
print(('Handle with select() : %10d / sec'):format(test(op_1)))
print(('Handle with table.pack: %10d / sec'):format(test(op_2)))

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