Lua noob

[SledgeHammer_999]

Hello I am writing Lua script for Aegisub but I have some problems with the language. I am used to coding in C++ only(as a hobby) and can't figure out many things in Lua. The error is in line 11 of the script. The message I get from Aegisub is this: [string "remove_unused_styles.lua"]:11: attempt to get length of local 'styles' (a nil value)

Here is the relevant link on the Aegisub forum: http://forum.aegisub.org/viewtopic.php?f=5&t=2944

And here is my code:

script_name = "Remove Unused Styles"
--script_description = "Displays a dialog that let's the user decide which unused styles to remove."
script_description = "Scan and remove the unused styles"
script_author = "sledgehammer_999"
script_version = "1.00"

function remove_unused_styles_macro(subtitles, selected_lines, active_line)
local styles
for i = 1, #subtitles do
if subtitles[i].class == "style" then
styles[#styles + 1].name = subtitles[i].name
styles[#styles + 1].index = i
end
end

--Styles definitions collected
--Now let's go over the dialogue lines and see which ones are used
for i = 1, #styles do
for k = 1, #subtitles do
styles[i].used = false
if subtitles[k].class == "dialogue" and subtitles[k].style == styles[i].name then
styles[i].used = true
break
end
end
end

--At this point we have marked the unused styles
--TODO: display a dialog and let the user decide which ones to remove. Currently don't know how to determine optimal size of the controls.

--remove the unused styles.
local styles_index
--This loop is redundant. It could be incorporated above, but it's placed here for when the dialog is implemented.
for i = 1, #styles do
if styles[i].used == false then
styles_index[#styles_index + 1] = i
end
end

--Now we have all the unused styles let's remove them and make and an undo point
subtitles.delete(unpack(styles_index))
aegisub.set_undo_point(script_name)
end

aegisub.register_macro(script_name, script_description, remove_unused_styles_macro)

[gmargo]

Try initializing the "styles" table:


local styles = {}
http://www.lua.org/pil/11.1.html

[SledgeHammer_999]

Let's say that I "solved" it. Look at the link in my first post.