How can find the missing bracket in this code?

Question

When I run the code it tells me there's an error which is ')' expected near '=':

function restartLvl()
    for i = 1, #balloonTexts do
        display.remove(balloonTexts[i])
        print ("restart level")
    end

    score.text = '0'
    ballRemain.text = '3'
    balloonText = {}
    createBalloons(1, 3)

    if (askUser.isVisible = true) then  --this is the line where the error occured
        askUser.isVisible = false
    end

    if (yesBtn.isVisible = true) then
        yesBtn.isVisible = false
    end

    if (noBtn.isVisible = true) then
        noBtn.isVisible = false
    end
end

I don't know how it is still missing a ')', because I closed all the brackets.

Basswood

Answer 1

= is the assignment operator, == is the operator to test equality. Change it to:

if (askUser.isVisible == true) then
    askUser.isVisible = false
end

And all the others as well. The brackets () can be ommited for simplicity:

if askUser.isVisible == true then
    askUser.isVisible = false
end

If the value is a boolean, you can also do this because all values that are not nil or false are treated as true.

if askUser.isVisible then
    askUser.isVisible = false
end

Rodolphe

Strike "If the value is a boolean". – Riptide

It works as well if the value of NOT a boolean. However, it's not exactly equivalent to the condition in the question (tests explicitly if the value is true). – Rodolphe

Yes, you're right. The mentioning of nil threw me off because nil is not boolean. Your statement is nuanced but correct. – Riptide

The stylistic pattern that the question asker uses "expression == true" and "expression == false" is a curious but not uncommon one. Perhaps it should be avoided in Lua. In general, the only time I see it making sense is where it improves readability but in most such cases, renaming a field, function or variable would be a better way. if askUser.isVisible then reads just fine to me. – Riptide

Answer 2

This is not related to your answer but

I recommend you to use lua glider IDE because this type error can be detect well by using this IDE.

Cash