How does Moses compare to Lua Fun?

[AVHon]

Apart from being more active, how does Moses compare to Lua Fun?

[stuta]

This project is alive and Luafun is dead, but Moses does not do things in lazy way. Performance difference is huge, so I continue to use Luafun that works great.

But I wish that code could be borrowed from Luafun. Some performance tests here: #58

[jtarchie]

Lua Fun was specifically designed to take advantage of the JIT in LuaJIT. I am not able to take advantage of the LuaJIT in my project as I am using the golang fork of Lua runtime. That means Lua Fun does not make sense for me.

[stuta]

Lazy evaluation has nothing to do with Luajit. Lazy libraries just do much less iterations than non-lazy versions and that's the reason why they are so much faster. In my quick test luafun is 6667 times faster than moses using PUC Lua.

-- fn-test.lua
local _ = require "moses" -- https://github.com/Yonaba/Moses/blob/master/doc/tutorial.md
local fn = require "fun" -- https://github.com/rtsisyk/luafun

local arr = {}
math.randomseed(os.time())
for i = 1, 10^6 do
  local rand = math.random(1, 100)
  arr[i] = {rand = rand, str = string.rep("x", rand)}
end

local function filterFn(rec)
  return rec.rand % 2 == 0
end
local function mapFn(rec)
  return rec.rand + 0.1
end

local time1 = os.clock()
local gen1 = fn.iter(arr):filter(filterFn):map(mapFn):take(3):totable()
time1 = os.clock() - time1
print(string.format('%.6f seconds: %s', time1, table.concat(gen1, ', ')))
local time2 = os.clock()
local gen2 = _(arr):filter(filterFn):map(mapFn):take(3):value()
time2 = os.clock() - time2
print(string.format('%.6f seconds: %s', time2, table.concat(gen2, ', ')))
print(string.format("time1: %.6f / time2: %.6f, luafun is %.0f times faster than moses", time1, time2, time2/time1))

Luajit 2.1:
0.000028 seconds: 48.1, 72.1, 52.1
0.104055 seconds: 48.1, 72.1, 52.1
time1: 0.000028 / time2: 0.104055, luafun is 3716 times faster than moses

PUC Lua 5.1:
0.000058 seconds: 90.1, 38.1, 78.1
0.386687 seconds: 90.1, 38.1, 78.1
time1: 0.000058 / time2: 0.386687, luafun is 6667 times faster than moses

[denisdemaisbr]

wrong way bench. it dont make sense.

[nagolove]

wrong way bench. it dont make sense.

@denisdemaisbr Hi, can you explain why bench is wrong? Or can you give better bench? Thanks.

[sebshader]

afaict I think the main difference is that moses always creates intermediate tables, but luafun mainly works with iterators themselves?