Lua in fsmapper

fsmapper incorporates a Lua script interpreter. This section provides Lua-related information necessary for writing Lua scripts as configuration files for fsmapper. However, it does not delve into the specifics of Lua language usage, so please refer to the Lua 5.4 Reference Manual for details on Lua itself.

Lua Version

Verion
5.4.8

Available Lua Standard Libraries

The following libraries from the Lua standard library are enabled by default.

Name	Description
basic	Basic functions
package	Basic facilities for loading modules
string	String manipulation
table	Table manipulation
math	Mathematical functions

If you want to use libraries other than those listed above in the configuration file or if you want to disable certain libraries for memory working set efficiency, you can change these settings on the settings page from the default configuration.

Module Search Path

Lua scripts in fsmapper can load Lua modules and Lua C modules using require(). Which modules can be found by require() is determined by Lua's module search path.

Default Search Path in fsmapper

When fsmapper starts, it initializes the following Lua variables:

• package.path: Paths used to search for pure Lua modules (.lua files).

• package.cpath: Paths used to search for compiled native libraries (.dll files).

These search paths are configured so that Lua modules and Lua C modules can be loaded relative to the directory where the user-specified Lua script is located.

As a result, Lua files and Lua C modules placed in the same directory as the script, or in its subdirectories, can be loaded with require() without any additional configuration.

-- mymodule.lua is located in the same directory as the script
local mymodule = require("mymodule")

Lua C modules are handled in the same way and are also searched relative to the script location.

Loading Modules from Other Locations

If you want to load modules located outside the script directory, you must explicitly modify the module search path within your Lua script.

This behavior is not specific to fsmapper, but follows standard Lua semantics.

-- Add a search path for Lua modules
package.path = package.path .. ";/path/to/lua/modules/?.lua"

-- Add a search path for Lua C modules
package.cpath = package.cpath .. ";/path/to/lua/modules/?.dll"

After updating these paths, modules in the specified directories can be loaded using require().

note

fsmapper exposes directory path variables such as mapper.script_dir, mapper.profile_dir, and mapper.saved_games_dir.

These variables can be used when extending package.path or package.cpath, for example:

package.path = package.path .. ";" .. mapper.script_dir .. "/modules/?.lua"

Using these variables helps avoid hard-coded paths and improves portability of Lua scripts across different environments.