Better Way to Find Length of Dictionary Excluding Functions (ModuleScript)

Help and Feedback Scripting Support
#1

Basically, I am creating a ModuleScript to store questions and answers in different subjects. Here is an example:

local questions = {
	["Math"] = {
		["What is 9 + 10?"] = "19",
		["What shape has 5 sides?"] = "pentagon",
		["What is the perimeter of a circle called?"] = "circumference"
	},
	["Science"] = {
		["What stage of the water cycle is rain/snow/hail?"] = "precipitation",
		["What is the first element of the periodic table?"] = "hydrogen",
		["How many bones are in the human body?"] = "206"
	},
	["English"] = {
		["What figure of language compares 2 things using like or as?"] = "simile",
		["What is the name of a word that describes an action? (ex. run, walk)"] = "verb",
		["How many letters are in the English alphabet?"] = "26"
	}
}

I used a ModuleScript for this because I want to have functions for the module, and one of them is getting the length of the dictionary, and this is it:

function questions.getSubjectAmount()
	local subjectAmount = 0
	
	for subject, questions in pairs(questions) do
		subjectAmount += 1
	end
	
	return subjectAmount
end

However, since I’m also storing functions in the dictionary, it will count those too as a “subject”.

I don’t want this to happen, and I could just check whether every item in my dictionary isn’t a function, but this feels like a very wrong way to do it.

Is there a better way to store this without having to check whether or not every item in my dictionary is a function or not? Or is that the way to do it? I don’t have a lot of experience with ModuleScripts, btw.

#2

Then I believe you have a design flaw. A table of data should only have data and nothing else. Consider isolating it and keep the functions in a separate table.

2 Likes
#3

Yes, do this and have the functions be in a metatable preferably.

#5

I suggest doing the things mentioned above; BUT, its still possible to do what you asked.

function questions.getSubjectAmount()
	local subjectAmount = 0
	
	for subject, questions in pairs(questions) do
		-- EDIT*: Not sure how your table functions are structured. Could possibly be typeof(questions)
		if typeof(subject) == "function" then
			continue
		end
		subjectAmount += 1
	end
	
	return subjectAmount
end
#6

they already knew that but are looking for alternatives

#7

Yea but that doesn’t make much sense when they’re already iterating through the table to count it…

#8

maybe make a separate table for it entirely, if not that then separate it like this

local questions = {
    questions = {},
    functions = {},
}

and if not that, then I’d do what @azqjanna said

#9

I believe I’m highly confused here, but can’t you just do local Length = #ExampleTable?

#10

doing the len operator on this dictionary would just be 0

#11

That only works for arrays (tables indexed with numbers, not strings).

#12

Thanks everyone for your support!

I’m going to do what @Prototrode said and what @azqjanna by creating a separate metatable for my main questions table in the ModuleScript. After reading up on metatables for a while now, I’ll definitely be using them in the future!

#13

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.