Stash

Tool for keeping data across code reloads

There are several techniques for keeping data across code reloads. (Code reload - cleaning up package.loaded[<module name>] with following require '<module name>')

1. Store value in global

local data
if not MY_DATA then
    MY_DATA = {}
end
local data = MY_DATA

• May not work under strict
• Suffers from possibility to override it from somewhere

2. Store value in _G using rawget/rawset

local data
if not rawget(_G,'MY_DATA') then
    rawset('MY_DATA',{})
end
local data = MY_DATA

• Suffers from possibility to override it from somewhere

3. Store value in _G using rawget/rawset and give it unwritable name (use \0 for example)

local data
if not rawget(_G,'\0MY_DATA') then
    rawset('\0MY_DATA',{})
end
local data = rawget(_G,'\0MY_DATA')

This will work rather good and this technique is used by stash. But using this from a lot modules will cause _G pollution

So, for easy use the stash was created.

Simple interface allows to get the same stash by name

local mystash = require'stash'.get('stash name')

Or with use of overloaded call

local mystash = require'stash'('stash name')

From within module, name of module in ... may be used as name without collision with _G

local mystash = require'stash'(...)

There are also 2 more methods:

require'stash'.del('stash name') -- to delete some stash
require'stash'.clear('stash name') -- to empty some stash