24 posts
Posted 10 March 2013 - 03:23 PM
-- Just for example
term = loadstring("term.")
method = loadstring(method)
term()method()
-- How would you do the term.method WITHOUT putting it all in one loadstring?
This is a read-only snapshot of the ComputerCraft forums,
taken in April 2020.
Combine 2 Functions?
Started by Sphexish, 10 March 2013 - 02:23 PM
1619 posts
Posted 10 March 2013 - 03:36 PM
I'm not sure I understand your question. You can concatenate variables using "..". For example:
print("What is your name?")
name = read()
print("Hello, "..name)
24 posts
Posted 10 March 2013 - 03:51 PM
Nonono..
loadstring makes a function out of a string.
loadstring makes a function out of a string.
func = loadstring('term.write("hello")')
func()
1619 posts
Posted 10 March 2013 - 05:44 PM
Nonono..
loadstring makes a function out of a string.func = loadstring('term.write("hello")') func()
Please explain what you're trying to do, I'm not sure I understand.
2005 posts
Posted 10 March 2013 - 06:21 PM
You can make a function that takes the result of another function, and then call them like "functiona(functionb())" But other than that you're kinda stuck. The string that you pass into a loadstring has to describe a valid function, even if all the function does is return a value of some kind (eg. loadstring("return 5")).
What you seem to be trying to do is find a way to index an API using a variable. This is quite simple, just do something like this:
What you seem to be trying to do is find a way to index an API using a variable. This is quite simple, just do something like this:
method = "write"
term[method]("something to write")
1688 posts
'MURICA
Posted 10 March 2013 - 08:27 PM
I guess you could try something like this.
Something like that.
local env = getfenv()
local api = loadstring 'return term' () -- wow i love how valid this is !!!
local func = loadstring 'return "write"' ()
api[func]()
Something like that.
2005 posts
Posted 10 March 2013 - 10:35 PM
Kingdaro is making a funny here. Yes, you can do that. But please don't.
797 posts
Posted 11 March 2013 - 12:43 AM
Wow I never knew you could do this…is it possible to do the reverse, i.e. making a string out of a function?
7508 posts
Australia
Posted 11 March 2013 - 01:08 AM
Not quite. there is string.dump which turns the code we all know and love and type, into Lua Bytecode.Wow I never knew you could do this…is it possible to do the reverse, i.e. making a string out of a function?
797 posts
Posted 11 March 2013 - 01:14 AM
Hmm, shame…I would have loved to be able to find & print the code inside a function…. What does Lua Bytecode do? Is it just binary code?
758 posts
Budapest, Hungary
Posted 11 March 2013 - 01:18 AM
Hmm, shame…I would have loved to be able to find & print the code inside a function…. What does Lua Bytecode do? Is it just binary code?
Yup - The bright side of using Lua bytecode is that you can load it via loadstring just like the usual Lua source code.
997 posts
Wellington, New Zealand
Posted 11 March 2013 - 01:18 AM
Lua source code is compiled into Lua bytecode. Once it's been compiled, the original source code isn't saved anywhere.
Bytecode is like machine code, but designed to be efficient for a particular language rather than a particular CPU. The bytecode is what is stored in memory and what gets run by Lua.
Bytecode is like machine code, but designed to be efficient for a particular language rather than a particular CPU. The bytecode is what is stored in memory and what gets run by Lua.
797 posts
Posted 11 March 2013 - 01:24 AM
Ok so if I understand correctly…
local k = string.dump( myfunction )
print( loadstring( k ) )
--this will print the contents of myfunction?
758 posts
Budapest, Hungary
Posted 11 March 2013 - 01:29 AM
Ok so if I understand correctly…local k = string.dump( myfunction ) print( loadstring( k ) ) --this will print the contents of myfunction?
No. That will print "function: [pointer here]". But
print(k)
797 posts
Posted 11 March 2013 - 01:38 AM
Ah, is there string.un_dump_into_normal_string_that_can_be_printed( ) by any chance? Bytecode is just a load of question marks on the cc screen to meOk so if I understand correctly…local k = string.dump( myfunction ) print( loadstring( k ) ) --this will print the contents of myfunction?
No. That will print "function: [pointer here]". ButWOULD print the contents of myfunction (the bytecode, of course).print(k)
758 posts
Budapest, Hungary
Posted 11 March 2013 - 01:40 AM
Lua source code is compiled into Lua bytecode. Once it's been compiled, the original source code isn't saved anywhere.
Bytecode is like machine code, but designed to be efficient for a particular language rather than a particular CPU. The bytecode is what is stored in memory and what gets run by Lua.
So nope.
2005 posts
Posted 11 March 2013 - 11:30 AM
Well, you could write a decompiler if you were determined…but I'm not sure why you ever would. Lua is an interpreted language, so you should normally have access to the original Lua text somewhere.