`TypeError: Cannot add indexer to table`

Help and Feedback Scripting Support
#1

Hello, I tried using keyof<> and typeof() functions in my code but it doesn’t work and I don’t understand the error message.

Here is my code: 
function unicodeProgressBar.generateBar(value: number, minRangeValue: number, maxRangeValue: number, length: number, background_block: keyof<typeof(CONSTANTS.BACKGROUND_BLOCKS)>): string
	local bar: string = ""

	local normalizedValue: number = (value - minRangeValue) / (maxRangeValue - minRangeValue)
	local scaledToLengthValue: number = length * normalizedValue

	local scaledToLengthValueWhole: number, scaledToLengthValueMantissa: number = math.modf(scaledToLengthValue)

	local quantizedScaledValueMantissa: number = quantize(scaledToLengthValueMantissa, CONSTANTS.INTERVAL)

	for _ = 1, scaledToLengthValueWhole, 1 do
		bar ..= CONSTANTS.BLOCKS[8]
	end
	bar ..= CONSTANTS.BLOCKS[quantizedScaledValueMantissa * CONSTANTS.INTERVAL_DENOMINATOR]
	
	for _ = 1, length - scaledToLengthValueWhole, 1 do

--
		bar ..= CONSTANTS.BACKGROUND_BLOCKS[background_block] -- HERE IS THE ERROR
--

	end
	
	return bar
end
Here is the CONSTANTS module: 
local CONSTANTS = {}

CONSTANTS.BLOCKS			=	{[0] = "" --[[ Necessary as indices start at 1 ]], "▏","▎","▍","▌","▋","▊","▉","█"} -- to self: smooth right to left bars are not possible as the necessary characters do not exist in unicode
CONSTANTS.BACKGROUND_BLOCKS	=	{
    ["NONE"] = "", 
    ["TRANSPARENT"] = " ", 
    ["MINIMAL"] = "░", 
    ["MEDIUM"] = "▒", 
    ["MEDIUM_REVERSED"] = "�", 
    ["FULL"] = "▓"
}

CONSTANTS.INTERVAL		        =	1/8
CONSTANTS.INTERVAL_DENOMINATOR	=	8

return CONSTANTS

I put my CONSTANTS in a separate script as to avoid cyclic requires.
Pls help.

#2

Cannot add indexer to table means you’re trying to index a table with an invalid data type. I don’t know where you are getting keyof<> from but as far as i’m aware that is not a valid operator in Lua?

#3

It is valid in the new luau type solver.

#4

I see it now, I was unaware they already put the new solver on beta. Let me make a quick repro of this and I’ll see what I can figure out

1 Like
#5

Can I get a quick rundown of what the background_block variable the generateBar function gets fed?

#6

It can get fed these:
"FULL" | "MEDIUM" | "MEDIUM_REVERSED" | "MINIMAL" | "NONE" | "TRANSPARENT"

#7

odd, in my reproduction of your script:

Repro 
local CONSTANTS = {}

CONSTANTS.BLOCKS			=	{[0] = "" --[[ Necessary as indices start at 1 ]], "▏","▎","▍","▌","▋","▊","▉","█"} -- to self: smooth right to left bars are not possible as the necessary characters do not exist in unicode
CONSTANTS.BACKGROUND_BLOCKS	=	{
	["NONE"] = "", 
	["TRANSPARENT"] = " ", 
	["MINIMAL"] = "░", 
	["MEDIUM"] = "▒", 
	["MEDIUM_REVERSED"] = "�", 
	["FULL"] = "▓"
}

CONSTANTS.INTERVAL		        =	1/8
CONSTANTS.INTERVAL_DENOMINATOR	=	8

function generateBar(value: number, minRangeValue: number, maxRangeValue: number, length: number, background_block: keyof<typeof(CONSTANTS.BACKGROUND_BLOCKS)>): string
	local bar: string = ""

	local normalizedValue: number = (value - minRangeValue) / (maxRangeValue - minRangeValue)
	local scaledToLengthValue: number = length * normalizedValue

	local scaledToLengthValueWhole: number, scaledToLengthValueMantissa: number = math.modf(scaledToLengthValue)

	local quantizedScaledValueMantissa: number = 1 -- Replaced cuz i dont have the quantize function

	for _ = 1, scaledToLengthValueWhole, 1 do
		bar ..= CONSTANTS.BLOCKS[8]
	end
	bar ..= CONSTANTS.BLOCKS[quantizedScaledValueMantissa * CONSTANTS.INTERVAL_DENOMINATOR]

	for _ = 1, length - scaledToLengthValueWhole, 1 do

		--
		bar ..= CONSTANTS.BACKGROUND_BLOCKS[background_block] -- HERE IS THE ERROR
		--

	end

	return bar
end

print(generateBar(1, 0, 100, 10, "FULL"))

No such error as what you are getting is appearing for me. I did leave away the quantize function but I doubt that has any effect.

1 Like
#8

What if I give you my place file? The module is in replicatedstorage

#9

If you’re willing to do so then yes I’d like to look at your place file

#10

unicodeprogressbar.rbxl (65.6 KB)
Here it is. Thanks for being invested btw

#11

Thank you. I’ll poke around and see what I can find. My hunch is that it’s a quirk with the fact you’re using a module script to store the unicode data but I’m not sure yet

1 Like
#12

update: works perfectly fine in my studio right now:

image
image2016×1097 125 KB

#13

Oh. Is there no linting in the modulescript too?

#14

I’ve done a bunch of digging and this pending bug seems to be your case: Release Notes for 647 | Documentation - Roblox Creator Hub.
"Fixes new solver crashes related to unions of tables. Users might see false positive errors related to “Cannot add indexer to table”. "

2 Likes
#15

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