Short IF Statement in Lua

[mirage]

In Objective-C I could take something like

if (foo){
print("true");
}else{
print("false");
}

and turn it into

print( (foo?"true":"false") );

Does Lua have anything similar to this?

[vrld]

Yes: and and or work on any values, not just booleans:

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if foo then print("true") else print("false") end
-- equal to
print(foo and "true" or "false")

[mirage]

I'm noticing that when I try to concatenate a string to this, it doesn't work

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print("1st run: " ..(initialRun and "Yes" or "No"))

Without the parentheses, an error is thrown for string to boolean concatenation

With the parentheses, initialRun returns TRUE no matter what.

[Rad3k]

I'm noticing that when I try to concatenate a string to this, it doesn't work

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print("1st run: " ..(initialRun and "Yes" or "No"))

Without the parentheses, an error is thrown for string to boolean concatenation

With the parentheses, initialRun returns TRUE no matter what.

Strange, because your code works well for me.
And without parentheses, the concatenation operator gets precedence over logical ones, so it tries to concatenate "1st run:" with initialRun value (which is probably a boolean in your case).

[vrld]

Works for me:

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> initialRun = false
> print("1st run: " ..(initialRun and "Yes" or "No"))
1st run: No
> initialRun = true 
> print("1st run: " ..(initialRun and "Yes" or "No"))
1st run: Yes

Without the parentheses, an error is thrown for string to boolean concatenation

You should take another look at Programming in Lua chapter 3: Expressions, especially section 3.5: Precedence.

[mirage]

I found the problem. I was expecting "love.filesystem.mkdir()" to return false if the folder already existed. I will need to use "love.filesystem.exists()" for that.

Thanks so much!