Most Annoying Error In Playground – WWDC20

After getting familiar with the basics of Playground, I found that it can use almost in the same way as normal Xcode project, except one thing – unknown error.

I’ve finished playable part of the TicTacToe game. The game allows randomizing who starts first and check game status, after the finished game it starts from the beginning.

It also checks if there is drawn, quite a common situation in standard 3×3 board.

During this, I encountered one very annoying error.


expression failed to parse, unknown error

It doesn’t say anything that is wrong. To be funnier, it shows in the Console.

My solution to that is Undoing (Command + Z ) and every time checking if code works.

Another is commenting and uncommenting and checking if this line of code causes the error.