Condition evaluating incorrectly (Lua 4)

user_330663 0
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I am trying to use this function in Lua 4:

function ternary(cond, T, F)
    if cond then return T else return F end
end

In this context:

loadHW1 = false
print(ternary(loadHW1 == true, "this should not appear", nil))

However, the text always gets printed when instead I expect the result to be nil. What am I doing wrong? Thanks.

[ed]

I switched to this but still get a "this is true" result:

loadHW1 = 0
print(ternary(loadHW1, "this is true", "this is false"))
ternary lua
1 Answers

Lua 4 doesn't have Booleans: they were introduced in Lua 5.

In Lua 4, only nil is false; anything else, including 0, is true.

In your code, false and true are being interpreted as undefined global variables and so both evaluate to nil. Therefore, loadHW1 == true becomes nil == nil, which is true, and so ternary receives 1 for cond.

If you want to use false and true in Lua 4, define them as follows:

false = nil
 true = 1
user_1070900
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