Unable to set global varable in Hammerspoon Lua
Mikeno-Philippe opened this issue · comments
The following code runs well under Lua:
counter, offset = 0, 1
function reset()
counter = 0
print(counter)
end
function inc()
counter = counter + offset
print(counter)
end
reset() --> 0
inc() --> 1
inc() --> 2
reset() --> 0
... but running the same code under Hammerspoon Lua doesn't work as expected, the last print statement gives 2, meaning that the global variable counter has not been reseted.
Thx for your help
I found how to solve this issue using rawset
function declare (name, initval)
rawset(_G, name, initval or false)
end
counter, offset = 0, 1
declare("counter", 0)
declare("offset", 1)
It works fine on my Hammerspoon. Do you have any code in your config (or loaded Spoons) that would be setting a metatable on the global environment?
What does this code print for you when pasted into the console?
local mt = getmetatable(_G)
if mt then
print(hs.inspect(mt))
for k,v in pairs(mt) do
if type(v) == 'function' then
local info = debug.getinfo(v)
if what ~= 'C' then
print(hs.inspect(info))
end
end
end
else
print('no metatable on _G')
end
Weird… When you ran into the issue, was it in the console or the config file? If it was the config, try putting the code I sent there instead of in the console and see if that prints anything different.
Actually, just in case _G
isn't what's getting used for some reason, can you try using this version instead?
local function checkMT(name, tbl)
local mt = getmetatable(tbl)
if mt then
print(hs.inspect(mt))
for k,v in pairs(mt) do
if type(v) == 'function' then
local info = debug.getinfo(v)
if what ~= 'C' then
print(hs.inspect(info))
end
end
end
else
print('no metatable on '..name)
end
end
checkMT('_G', _G)
if rawequal(_ENV, _G) then
print '_ENV is _G'
else
print '_ENV is not _G'
checkMT('_ENV', _ENV)
end
What about when you run it from within your reset
and/or inc
functions? Also, is there anywhere you're declaring counter
and/or offset
as local
s (or function argument names)?
I don't know of anything else that could interfere with setting global variables. As far as I know, Hammerspoon should be using an unmodified Lua interpreter.
The only other thing I can think of to try right now is moving your entire init.lua
file aside and making a new one with just the code from your initial post. If that works correctly, we can try to narrow down exactly where it starts breaking. If it still fails, I'm not sure what to do.
I see a couple of issues in that code that might explain why the counter isn't updating properly:
- I don't see a definition for that
setOffset
function anywhere, and even if it exists, any change it makes tooffset
will get overwritten by theoffset =
part of the menu item'sfn
- changing it to whateversetOffset
's return value was. - This version of
reset
doesn't seem to actually setcounter
at all - it just updates the menu's title and shows the alert. Also, it's settingoffset
toreset
's return value, which isnil
- meaning that any Increase/Decrease commands after that point will throw anattempt to perform arithmetic on a nil value
error and not actually change the counter.
These next two aren't directly related to the counter problem, but:
$
and^
aren't their own keys, at least on most keyboard layouts that I know of, so they don't have keycodes defined inhs.keycodes.map
and can't be passed directly tohs.hotkey.bind
like that. Assuming that they're Shift-4 and Shift-6 like on my keyboard, you'll need to do something like:
hyper = {"cmd","alt","ctrl"}
hyperShift = {"cmd","alt","ctrl","shift"}
hs.hotkey.bind(hyperShift, "4", function()
updateCounter(offset)
end)
hs.hotkey.bind(hyperShift, "6", function()
updateCounter(-offset)
end)
"Set offset (" .. offset .. ")"
: This title will get evaluated once when your config first runs, and won't update when theoffset
is changed. You can either include something like:
menuMenu[4].title = "Set offset (" .. offset .. ")"
menu:setMenu(menuMenu)
in your setOffset
function, or change menuMenu
to a function so it gets re-evaluated each time the menu opens:
function menuMenu()
return {
{ title = "Increase", fn = function() updateCounter(offset) end },
{ title = "Decrease", fn = function() updateCounter(-offset) end },
{ title = "-" },
{ title = "Set offset (" .. offset .. ")" , fn = function() offset = setOffset(offset) end },
{ title = "Reset counter", fn = function() offset = reset() end }
}
end
Glad to hear it's working for you.
Concerning both keys (« $ » and « ^ »), they are direct own keys on a French keyboard!
Gotcha. For some reason I wasn't sure if Hammerspoon knew that, though, but I see now that it does properly update hs.keycodes.map
to include $ and ^ when you're on that layout.