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POLua: Get function source
 

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    <p>I'm working on a system for serialization/deserialization, and I'm trying to get some really fancy stuff going with functions. My goal is to serialize objects containing functions in a human-readable and reversible manner (the serialized files will need processing after the loadfile() step). I need a way to get the actual source of a function, and it looks like I can't always do that with debug.getinfo(). </p> <p>I know that debug.getinfo() will give be the file and line where it was defined (or the source of the function, depending on its origin). Is there a way I can read the function text from that file? I'd be willing to use some kind of parser utilities to do so. Maybe there are Lua packages for parsing Lua code?</p> <p>Perhaps there's a way I can get loadfile() or require() to automatically retain function source somewhere?</p> <p>Yes, I know you can get all sorts of information out of debug.getinfo, but it was unable to deal with functions loaded through stdin...</p> <pre><code>uberblah@glade-m:~$ lua Lua 5.1.5 Copyright (C) 1994-2012 Lua.org, PUC-Rio &gt; a = function() print("hello, world!") end &gt; require("serpent") &gt; s = require("serpent") &gt; =s.block(debug.getinfo(a)) { currentline = -1, func = loadstring("LuaQ\000\000\000\000\000\000\000\000\000=stdin\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000A@\000\000@\000\000�\000\000\000\000\000\000\000\000\000\000\000print\000\000\000\000\000\000\000\000hello, world!\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000",'@serialized') --[[function: 0x2068a30]], lastlinedefined = 1, linedefined = 1, namewhat = "", nups = 0, short_src = "stdin", source = "=stdin", what = "Lua" } --[[table: 0x206cf80]] &gt; f = io.open("stdin", "r") &gt; =f nil </code></pre> <p>SOLUTION FOR SOURCE FROM STDIN... 1) Capture all STDIN, write it to a file 2) Load the information from that file, instead of from stdin 3) debug will track the function line numbers in that file</p>
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    1. COYou really going to use stdin (which is console input, so io.open("stdin") does not do what you want)? or a script that loads modules? If latter it may be easier. Why do you need this capability? Maybe there is another way. Also, if you use lhf's answer, you can read in the file specified in "source" and read the source directly (since you have linedefined etc).
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    2. COI'm aware that if it were not for this annoying need to get functions off of stdin I could load the functions with relative ease. However, I plan on using functions read from stdin because I'm writing a debug console for a videogame, and input from that console (written in C) is being redirected to stdin. I guess very few other people will need to read from stdin, and I can get some kind of buffer between the debug console and Lua (that buffer could be saved to a file for debug-ability). Sorry about the confusion
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    3. CO@Schollii The edits I made should clearly illustrate: io.open("stdin") returns nil because there is no such file! I am also aware that I can read the function if it came from a file, but this does not cover the stdin case. I accepted the answer because I can capture stdin myself, and copy its contents to a file I can later refer to.
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