Why won't some metamethods work properly?

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2 years ago

Edited 2 years ago

I'm using metamethods for my "Number Instance" module to act like real numbers. Most of the metamethods are working fine, except for these three: __eq, __le, and __lt. They are scripted the same way with __concat, __add, __sub, __mul, __div, __mod, and __pow, but they won't work properly as expected. I tried printing them in a script and this is what they printed:

01local NumberService = require(game:GetService("ReplicatedStorage"):WaitForChild("CustomServices")):GetService("NumberService")
02 
03local TestNumber = NumberService.new(50)
04 
05print("My number is " .. TestNumber) -- "My number is 50" (working) __concat
06print(-TestNumber) -- -50 (working) __unm
07print(TestNumber + 50) -- 100 (working) __add
08print(60 - TestNumber) -- 10 (working) __sub
09print(TestNumber * 2) -- 100 (working) __mul
10print(50 / TestNumber) -- 1 (working) __div
11print(TestNumber % 28) -- 22 (working) __mod
12print(2 ^ TestNumber) -- 1125899906842624 (working) __pow
13print(tostring(TestNumber)) -- "50" (working) __tostring
14print(50 == TestNumber) -- false (not working) __eq
15print(TestNumber < 60) -- attempt to compare table < number (not working) __lt
16print(TestNumber > 60) -- attempt to compare table > number (not working) __lt
17print(40 <= TestNumber) -- attempt to compare table <= number (not working) __le
18print(TestNumber >= 40) -- attempt to compare table >= number (not working) __lt
19print(#TestNumber) -- attempt to get length of a number value (working) __len

This is the expected output to the lines that are not working

1print(50 == TestNumber) -- true
2print(TestNumber < 60) -- true
3print(TestNumber > 60) -- false
4print(40 <= TestNumber) -- true
5print(TestNumber >= 50) -- true

And this is the module script

001newNumber.__index = NumberInstance
002newNumber.__concat = function(a, b)
003    local isNumberInstance1 = typeof(a):lower() == "table" and a.Number ~= nil
004    local isNumberInstance2 = typeof(b):lower() == "table" and b.Number ~= nil
005 
006    if isNumberInstance1 and isNumberInstance2 then
007        return a.Number .. b.Number
008    elseif isNumberInstance1 and not isNumberInstance2 then
009        return a.Number .. b
010    elseif not isNumberInstance1 and isNumberInstance2 then
011        return a .. b.Number
012    elseif not isNumberInstance1 and not isNumberInstance2 then
013        return a .. b
014    end
015end
016newNumber.__unm = function(self)
017    return -(self.Number)
018end
019newNumber.__add = function(a, b)
020    local isNumberInstance1 = typeof(a):lower() == "table" and a.Number ~= nil
021    local isNumberInstance2 = typeof(b):lower() == "table" and b.Number ~= nil
022 
023    if isNumberInstance1 and isNumberInstance2 then
024        return a.Number + b.Number
025    elseif isNumberInstance1 and not isNumberInstance2 then
026        return a.Number + b
027    elseif not isNumberInstance1 and isNumberInstance2 then
028        return a + b.Number
029    elseif not isNumberInstance1 and not isNumberInstance2 then
030        return a + b
031    end
032end
033newNumber.__sub = function(a, b)
034    local isNumberInstance1 = typeof(a):lower() == "table" and a.Number ~= nil
035    local isNumberInstance2 = typeof(b):lower() == "table" and b.Number ~= nil
036 
037    if isNumberInstance1 and isNumberInstance2 then
038        return a.Number - b.Number
039    elseif isNumberInstance1 and not isNumberInstance2 then
040        return a.Number - b
041    elseif not isNumberInstance1 and isNumberInstance2 then
042        return a - b.Number
043    elseif not isNumberInstance1 and not isNumberInstance2 then
044        return a - b
045    end
046end
047newNumber.__mul = function(a, b)
048    local isNumberInstance1 = typeof(a):lower() == "table" and a.Number ~= nil
049    local isNumberInstance2 = typeof(b):lower() == "table" and b.Number ~= nil
050 
051    if isNumberInstance1 and isNumberInstance2 then
052        return a.Number * b.Number
053    elseif isNumberInstance1 and not isNumberInstance2 then
054        return a.Number * b
055    elseif not isNumberInstance1 and isNumberInstance2 then
056        return a * b.Number
057    elseif not isNumberInstance1 and not isNumberInstance2 then
058        return a * b
059    end
060end
061newNumber.__div = function(a, b)
062    local isNumberInstance1 = typeof(a):lower() == "table" and a.Number ~= nil
063    local isNumberInstance2 = typeof(b):lower() == "table" and b.Number ~= nil
064 
065    if isNumberInstance1 and isNumberInstance2 then
066        return a.Number / b.Number
067    elseif isNumberInstance1 and not isNumberInstance2 then
068        return a.Number / b
069    elseif not isNumberInstance1 and isNumberInstance2 then
070        return a / b.Number
071    elseif not isNumberInstance1 and not isNumberInstance2 then
072        return a / b
073    end
074end
075newNumber.__mod = function(a, b)
076    local isNumberInstance1 = typeof(a):lower() == "table" and a.Number ~= nil
077    local isNumberInstance2 = typeof(b):lower() == "table" and b.Number ~= nil
078 
079    if isNumberInstance1 and isNumberInstance2 then
080        return a.Number % b.Number
081    elseif isNumberInstance1 and not isNumberInstance2 then
082        return a.Number % b
083    elseif not isNumberInstance1 and isNumberInstance2 then
084        return a % b.Number
085    elseif not isNumberInstance1 and not isNumberInstance2 then
086        return a % b
087    end
088end
089newNumber.__pow = function(a, b)
090    local isNumberInstance1 = typeof(a):lower() == "table" and a.Number ~= nil
091    local isNumberInstance2 = typeof(b):lower() == "table" and b.Number ~= nil
092 
093    if isNumberInstance1 and isNumberInstance2 then
094        return a.Number ^ b.Number
095    elseif isNumberInstance1 and not isNumberInstance2 then
096        return a.Number ^ b
097    elseif not isNumberInstance1 and isNumberInstance2 then
098        return a ^ b.Number
099    elseif not isNumberInstance1 and not isNumberInstance2 then
100        return a ^ b
101    end
102end
103newNumber.__tostring = function(self)
104    return tostring(self.Number)
105end
106newNumber.__eq = function(a, b)
107    local isNumberInstance1 = typeof(a):lower() == "table" and a.Number ~= nil
108    local isNumberInstance2 = typeof(b):lower() == "table" and b.Number ~= nil
109 
110    if isNumberInstance1 and isNumberInstance2 then
111        return a.Number == b.Number
112    elseif isNumberInstance1 and not isNumberInstance2 then
113        return a.Number == b
114    elseif not isNumberInstance1 and isNumberInstance2 then
115        return a == b.Number
116    elseif not isNumberInstance1 and not isNumberInstance2 then
117        return a == b
118    end
119end
120newNumber.__lt = function(a, b)
121    local isNumberInstance1 = typeof(a):lower() == "table" and a.Number ~= nil
122    local isNumberInstance2 = typeof(b):lower() == "table" and b.Number ~= nil
123 
124    if isNumberInstance1 and isNumberInstance2 then
125        return a.Number < b.Number
126    elseif isNumberInstance1 and not isNumberInstance2 then
127        return a.Number < b
128    elseif not isNumberInstance1 and isNumberInstance2 then
129        return a < b.Number
130    elseif not isNumberInstance1 and not isNumberInstance2 then
131        return a < b
132    end
133end
134newNumber.__le = function(a, b)
135    local isNumberInstance1 = typeof(a):lower() == "table" and a.Number ~= nil
136    local isNumberInstance2 = typeof(b):lower() == "table" and b.Number ~= nil
137 
138    if isNumberInstance1 and isNumberInstance2 then
139        return a.Number <= b.Number
140    elseif isNumberInstance1 and not isNumberInstance2 then
141        return a.Number <= b
142    elseif not isNumberInstance1 and isNumberInstance2 then
143        return a <= b.Number
144    elseif not isNumberInstance1 and not isNumberInstance2 then
145        return a <= b
146    end
147end
148newNumber.__len = function(self)
149    error("attempt to get length of a number value", 0)
150end
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Why won't some metamethods work properly?

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