CODEWITHSUNDEEP
lua
Igor K.
Igor K.

Reputation: 877

Lua: How to take only certain functions from the library?

I have library file service_functions.lua. There are hundreds of functions in it.

function foo1()
------------
end

function foo2()
------------
end

and so on

I don't want to load all functions.
Now I do:

dofile(script_path.."\\service_functions.lua")

and get all of them.
How to get only specific functions?

Upvotes: 1

Views: 158

Answers (3)

Mike V.
Mike V.

Reputation: 2205

but if, as you wrote in the question, you need minimal memory load, then maybe my version will come in handy module:

local arg={...}

local function foo1() print("foo1")
end

local function foo2() print("foo2")
end

local function foo3() print("foo3")
end

local function foo4() print("foo4")
end
local M = {foo1=foo1, foo2=foo2, foo3=foo3, foo4=foo4} 

if not arg[1] then return M     -- all
elseif type(arg[1])=="string" then
    local x = {} 
    x[arg[1]] = M[arg[1]] 
    return x                   -- 1 function by name
elseif type(arg[1])=="table" then 
    local res = {}
    for k,v in pairs(arg[1]) do
       res[v] = M[v]
    end
    return  res                 -- some functions
end

and return only what is needed from "hundreds" of functions

-- only 1 function loaded

local x = loadfile("funk.lua")("foo1")
x.foo1()

-- only 2 functions loaded
local x = loadfile("funk.lua")( { "foo1", "foo2"} )

x.foo1()
x.foo2()

-- all functions loaded

local x = loadfile("funk.lua")()
x.foo1()
x.foo2()
x.foo3()
x.foo4()

Upvotes: 2

Piglet
Piglet

Reputation: 28946

Remove any function you don't want/need from service_functions.lua or wrap the library with your own module as shown by lhf

You cannot execute just a part of a Lua file. The file is loaded and exectuted as one chunk.

Alternatively just live with it. It doesn't harm you to have more functions available.

Upvotes: 0

lhf
lhf

Reputation: 72332

Write your library as follows:

local M={}

function M.foo1()
------------
end

function M.foo2()
------------
end

return M

Then load the library with

local lib=dofile(script_path.."\\service_functions.lua")

and extract the functions you need with

foo1 = lib.foo1

Upvotes: 2

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