An experimental implementation of Lua 5.2 written solely in pure Erlang.
Some things which are known not to be implemented or work properly:
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label and goto
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tail-call optimisation in return
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only limited standard libraries
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proper handling of __metatable
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...
These are the interface functions in luerl.erl:
All functions optionally accept a Lua State parameter. The Lua State is the state of a Lua VM instance. It can be carried from one call to the next. If no State is passed in, a new state is initiated for the function call.
eval and do functions differ only in what they return. The do functions return results and a new Lua State, the eval functions return a tuple starting on 'ok' or 'error', then the result, or cause of error.
do --> {Result, State}
eval --> {ok, Result} | {error, Reason}
The 'compile' functions double the 'load' function, with but a different name.
Evaluate a Lua expression passed in as a string or binary, and return its result.
Load and execute a file, and return the result.
Evaluate a Lua expression and return its result, and the new Lua State.
Load and execute the Lua code in the file and return its result, and the new Lua State. Equivalent to doing luerl:eval("dofile('FileName')").
Parse a Lua chunk as string or binary, and return a compiled chunk.
Parse a Lua file, and return a compiled chunk.
Parse a Lua chunk as string or binary, and return a compiled chunk. Same as load/1.
Parse a Lua file, and return a compiled chunk. Same as loadfile/1.
Get a new Lua State = a fresh Lua VM instance.
Execute a compiled chunk.
Garbage collects the state and (todo:) does away with it.
Runs the (experimental) garbage collector on a state and returns the new state.
N.B. This interface is subject to change!
Examples
luerl:do("print(\"Hello, Robert(o)!\")"),
luerl:dofile("./examples/hello/hello.lua"),
{ok, Chunk} = luerl:load("print(\"Hello, Chunk!\")"),
State = luerl:start(),
{_Ret, _NewState} = luerl:do(Chunk, State),
For more examples see examples/hello/hello2.erl.
./hello.erl is a very brief example while examples/hello/hello2.erl is a comprehensive lists of most ways that come to mind of how to use the individual interface functions.
You can build and run these samples with:
make hello
make hello2
Currently implemented functions in the libraries:
_G _VERSION assert collectgarbage dofile eprint error getmetatable ipairs next pairs print rawequal rawget rawlen rawset select setmetatable tonumber tostring type
math.abs math.acos math.asin math.atan math.atan2 math.ceil math.cos math.cosh math.deg math.exp math.floor math.log math.max math.min math.pi math.pow math.rad math.sin math.sinh math.sqrt math.tan math.tanh
os.difftime os.getenv os.time
string.byte string.char string.len string.lower string.rep string.reverse string.upper
table.concat table.pack table.unpack