<input type="text" name="guessedWord" id="guessedWord" value="<?php ($POST) ? echo printMatching($POST["guessedWord"]) : echo ""; ?>" />
I'm pretty certain that the error is either in my use of the ?: operator or ($POST), as the following works just fine:
<input type="text" name="guessedWord" id="guessedWord" value="<?php echo printMatching($POST["guessedWord"]); ?>" />
It's most likely my use of the conditional operator, as the following doesn't work:
<input type="text" name="guessedWord" id="guessedWord" value="<?php (5 < 8) ? echo "yes, true" : echo "no, false"; ?>" />
Using "If ($_POST)" to see whether the form had been submitted to itself yet seemed to work for me in other places. As far as I can tell, though, my syntax for the conditional operator seems correct.