# Changelog

`hslua-core` uses [PVP Versioning][].

## hslua-core-2.3.1

Released 2023-03-17.

-   New module *HsLua.Core.Debug*: the module provides bindings to
    a subset of functions of the Lua debug interface. Currently
    the module only exports `getupvalue` and `setupvalue`, both of
    which are also re-exported from *HsLua.Core*.

## hslua-core-2.3.0

Released 2023-03-13.

-   The functions `loadfile`, `dofile`, and `dofileTrace` now
    expect the argument to be of type `Maybe FilePath`. The
    functions load from *stdin* when the argument is `Nothing`.

-   Added `setwarnf'` for simple warning messgae handling: The
    built-in method of setting a warn function is flexible but not
    straight-forward to use. The new `setwarnf'` function allows
    to set a Haskell action as a warning hook: the default warning
    behavior is kept in place, but, in addition to the default
    action, the hook is called on the concatenated warning
    messages. This can be used to plug Lua warnings into an
    application specific Haskell reporting system.

-   Export `GCManagedState`, `newGCManagedState`,
    `closeGCManagedState`, and `withGCManagedState` from
    `HsLua.Core`.

## hslua-core-2.2.1

Released 2022-06-19.

-   Ensure that loadfile works with umlauts in filepath: The OS
    does not necessarily expect filenames to be UTF-8 encoded,
    especially Windows. On non-Windows systems, the current file
    system encoding is now used to convert filenames to C
    strings. On Windows, the `CP_ACP` codepage is used, as
    required by the Windows API.

-   GC managed Lua state: Add new type `GCManagedState` and
    functions `newGCManagedState`, `closeGCManagedState`, and
    `withGCManagedState`. These allow to create and use a Lua
    state in flexible ways in that it does not require the state
    to be closed explicitly. The state will be closed when the
    respective variable is collected.

-   Require lua-2.2.1.

-   Relax upper bound for mtl, allow mtl-2.3.

## hslua-core-2.2.0

Released 2022-02-19.

-    Use lua-2.2.0, which requires Lua 5.4.

-    Rename `newuserdata` to `newuserdatauv` and let it take the
     number of associated uservalues as an additional argument.

     Similarly, `newhsuserdata` is now `newhsuserdatauv`.

-    Rename `getuservalue` and `setuservalue` to `getiuservalue`
     and `setiuservalue`, respectively. Like both functions now
     take an extra argument specifying the number of the uservalue
     that should be retrieved or set.

     It is now possible for `setiuservalue` to fail, so it returns
     a boolean to indicate whether the action was successful.

-    The `GCControl` type has been updated to match the new gc
     control:

     -   The GCStep constructor takes an argument "stepsize";
     -   constructors GCGen and GCInc have been added;
     -   constructors GCSetPause and GCSetStepMul have been removed.

## hslua-core-2.1.0

Released 29-01-2022.

-   The functions `rawget`, `rawgeti`, and `getref` now return the
    type of the value that was pushed to the stack.

-   A new function `checkstack'` is added to HsLua.Core.Auxiliary
    and exported from the main HsLua.Core module. The function
    throws an exception if the stack cannot be grown to
    accommodate a given number of elements; it is similar to
    `luaL_checkstack`.

-   Added function `requiref`, which safely wraps the unsafe
    `luaL_requiref` function.

-   New functions `pcallTrace`, `callTrace`, `dostringTrace`, and
    `dofileTrace`: behaves like the respective unsuffixed
    functions, but use a message handler that creates a stack
    traceback on error.

-   Added function `rotate`, wrapping `lua_rotate`.

-   Package helper `requirehs` signature changed to

    ``` haskell
    requirehs :: LuaError e
              => Name                 -- ^ modname
              -> (Name -> LuaE e ())  -- ^ openf
              -> LuaE e ()
    ```

    The function creating and pushing the module value now takes
    the module name as an argument. It also behaves more like
    `luaL_requiref` in that it reloads the module if the value in
    the LOADED table is falsy.

## hslua-core-2.0.0.2

Released 2021-11-03.

-   Fixed output of `pushTypeMismatchError` when there is no value
    at the given index. Previously the function would report the
    value as type `string` and now reports it as `no value`.

## hslua-core-2.0.0.1

Released 2021-10-29.

-   Fixed bug in pushTypeMismatchError. The function did not use
    an absolute stack index in one place, which sometimes lead to
    incorrect actual types being reported.

## hslua-core-2.0.0

Released 2021-10-21.

-   Error handling has been reworked completely. The type of
    exceptions used and handled by HsLua is now exposed to the
    type system. The type `Lua` makes use of a default error type.
    Custom error handling can be implemented by using the `LuaE`
    type with an exception type that is an instance of class
    `LuaError`.

-   Added new module HsLua.Core.Userdata. It contains thin
    wrappers around the functions available for creating
    Haskell-value-wrapping userdata objects.

-   Added new module HsLua.Core.Closures, containing functions to
    expose Haskell functions to Lua.

-   Reverted to using the auxlib `luaL_loadfile` function to load
    a Lua file. Previously files were opened and read in Haskell,
    but some functionality of the auxlib function was missing.

## hslua-core-1.0.0

Released 2021-02-27.

Extracted from hslua-1.3.0.

  [PVP Versioning]: https://pvp.haskell.org