Lua Boolean function return problem

[tkilshaw]

My attempts to build a function that returns a boolean value have failed.

This fails with an error on the line that includes the return statement.

function isCheese( food )

  if food == "cheese" then
    return true;
  else
    return false;
  end
end

If I quote "true" and "false" the function works but I get a string value and not a boolean value back.

Lua defines true and false as keywords. Am I doing something wrong or does Lua just not support returning booleans?

thanks,

Terry

[tkilshaw]

The problem was not in the function but in my attempt to use its return value in Dialog.Message.

The error message given was valid, but the line number for the error was not.

It said the error was in the On Startup script (Correct) but gave a line number of 8. At that point there were only 2 lines in the On Startup script. When I edited the called function to add an extra line, the error line number went up by one.

Terry

[Sergio_S]

Once I saw in a code that instead of true and false, you may return 1 (for true) and nil (for false) and even skip the whole part of else, that the end of the function will return nil.

Try it.

Sergio

[Sergio_S]

Additionally, depending on the version of Lua, only nil makes a condition false or, in the version 5.0, both nil and false make a condition false. Any other value (even 0 and "") makes it true.

So, maybe you can try also:

function isCheese( food )

  if food == "cheese" then
    return true;
  end
end