249 posts
In the universe
Posted 24 January 2013 - 01:53 PM
What are the metatables? Are they useful? Why to use them?Anything more to learn from them?
Thanks
Thanks
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[Lua] Metatables
Started by anonimo182, 24 January 2013 - 12:53 PM
392 posts
Christchurch, New Zealand
Posted 24 January 2013 - 01:56 PM
Tables, yes, Cause, Yes
You're Welcome :)/>
To be honest you can probably learn a lot more in the Lua Documentation, that's always the first place to look for advanced Lua stuff, Here I'll grab the link.
http://pgl.yoyo.org/.../2.8+Metatables
http://www.youtube.com/watch?v=CYxMfVy5W00
You're Welcome :)/>
To be honest you can probably learn a lot more in the Lua Documentation, that's always the first place to look for advanced Lua stuff, Here I'll grab the link.
http://pgl.yoyo.org/.../2.8+Metatables
http://www.youtube.com/watch?v=CYxMfVy5W00
7508 posts
Australia
Posted 24 January 2013 - 01:58 PM
392 posts
Christchurch, New Zealand
Posted 24 January 2013 - 02:01 PM
lua.org has so much nicer formatting than yoyo! <3
7508 posts
Australia
Posted 24 January 2013 - 02:02 PM
indeed the PIL is nice… I like how it breaks it up into small sections for ppl…lua.org has so much nicer formatting than yoyo! <3
404 posts
St. Petersburg
Posted 24 January 2013 - 02:57 PM
metatables are pretty much only useful for OOP, but when you get any deeper than your toes into OOP, they become essential in Lua.
392 posts
Christchurch, New Zealand
Posted 24 January 2013 - 03:06 PM
Metatables can also be used for sorcery!
Using the __index and __newindex, You could make a table represent your file system.
Not tested, and may have bugs. But the concept is excuse me, F'in awesome!
files["/startup"] then returns content, and you can set the content of the file with
files["/startup"] = 'print"ALL THE THINGS!"'
Using the __index and __newindex, You could make a table represent your file system.
local fs_mt = {}
fs_mt.__index = function(t, k)
if fs.exists(k) and not fs.isDir(k) then
local h = fs.open(k, "r")
if not h then return nil end
local v = h.readAll()
h.closeAl()
return v
else
return nil
end
end
fs_mt.__newindex = function(t,k,v)
local h = fs.open(k, "w")
if not h then return nil end
h.write(v)
h.close()
end
files = {}
setmetatable(files, fs_mt)
Not tested, and may have bugs. But the concept is excuse me, F'in awesome!
files["/startup"] then returns content, and you can set the content of the file with
files["/startup"] = 'print"ALL THE THINGS!"'