Category Archives: Lua

Rocket: A Lua Sqlite3 ORM manager

Posted on July 25, 2010 by Lee

Relational databases are designed so that they can both store and describe data. Most programming level APIs do wonderful jobs of maintaining the former aspect. I mean, what ORM doesn’t automatically map the insert method to the so very generic…

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See.lua – Documentation

Posted on July 24, 2010 by Lee

See.lua – A Lua introspection library

	> see(string)

	.byte(?)            .char(?)            .dump(?)            .find(?)
	.format(?)          .gfind(?)           .gmatch(?)          .gsub(?)
	.join(self, table, ...)                 .len(?)
	.lower(?)           .match(?)           .rep(?)             .reverse(?)
	.sub(?)             .upper(?)

Lua is a wonderful little language that lets you do…

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see.lua – Introspecting Lua objects

Posted on July 22, 2010 by Lee

As via its python equivalent, see.lua takes in an object and prints out a list of its elements as well as metatable methods in readable text.

> require "see"

> s = see(string)
.byte(?)            .char(?)            .dump(?)            .find(?)

…

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Tips and Tricks for Lua Beginners: Writing an at.exit registry

Posted on July 16, 2010 by Lee

It’s relatively simple to write a function that takes in a function and executes it once Lua terminates. 

at = {}
function at.exit(fn)
     getmetatable(newproxy(true)).__gc = fn
end
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Lua – Get a table of function arguments

Posted on July 16, 2010 by Lee

The lua standard libraries do not provide anything that helps you get the table of arguments for a given function. This can be accomplished by directly introspecting the bytecode of the function. The following snippet generates a function get_args that…

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Lua – Get number of parameters in a function

Posted on July 15, 2010 by Lee

The following snippet defines a function num_args(func) that returns the number of parameters within a function as a string:

num_args(function(a,b,c) end) --> 3

It also works with functions that have variable arguments:

num_args(function(a,...)

…

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Serializing Lua objects into Lua Code

Posted on July 13, 2010 by Lee

The following little snippet allows you to ‘pickle’ Lua objects directly into Lua code (with the exception of functions, which are serialized as raw bytecode). Metatable support is on the way, but for now, it should be useful enough.

Example…

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Lua Exception Handling

Posted on April 9, 2010 by Lee

Wouldn’t it be awsome if you could do something like

dofile "try"

try{
	function()
		a = a/a
	end
}.except(Exceptions.ValueError){
	function(_, exceptions, detail)
		print(detail)
	end
}

And get

lua:5: attempt to perform arithmetic on

…

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