uniham/system/registry.lua

-- Localize & Initialize
local register_hammer = uniham.register_hammer
local modpath = uniham.modpath
local registry = modpath..DIR_DELIM..'registry'
local depends = io.open(modpath..DIR_DELIM..'depends.txt', 'rb')
local log_prefix = '['..minetest.get_current_modname()..'] '


-- Check if a file exists
--
-- This function validates the existence of a file by trying to open the file
-- for reading. If this succeeds the file is present.
--
-- @param file_name The file name (path) to be checked
local file_exists = function (file_name)
    local f = io.open(file_name ,'r')
    if f ~= nil then
        io.close(f)
        return true
    else
        return false
    end
end


-- Check if the depends.txt file was read properly
--   Iterate over all lines
--     Check if the mod exists
--       Check if a registry file exists
--         dofile() the file and print a log message
if depends ~= nil then
    local lines = {}
    for line in depends:lines() do
        local modname = line:gsub('?', '')
        if minetest.get_modpath(modname) then
            local registry_file = registry..DIR_DELIM..modname..'.lua'
            if file_exists(registry_file) then
                dofile(registry_file)
                local message = 'Loaded built-in '..modname..' support'
                minetest.log('action', log_prefix..message)
            end
        end
    end
end