By jove, I think I got it...

Firstly, although I am not certain, I believe the error message is erroneously pointing to the wrong line $guess !~ m/[[:alpha:]]/ rather the error occurs in the elsif portion, where you have 

$guess =~ /[$good_guesses]/

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During the 1st pass, $good_guesses is either undefined, or set to a single letter (or multiple letter? doesn't matter).

On second pass, the $good_guesses is reset to a null string. 

$guess =~ /[$good_guesses]/

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gets translates to ... 
$guess =~ /[]/

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However, if I am not mistaken, character classes will accept a ']' as a valid element of the character class, if it is the first element of the class. So, the parser is taking the ']' as an element of the class, and then continues to look for the closing square bracket.

For whatever reason, if $good_guesses is undefined, the parser figures it out the way you meant. (UPDATE: Nope, that's not the reason, see update below)

To get your code to work, I re-initialized $good_guesses = undef; in your "reset_game" sub.

PS: I wrote my response after I got your program to work, but I did not actually go and read up on all the particulars of character classes in regular expressions, so I may not be entirely accurate.

Sandy

PS (again) ... That was fun!

UPDATE: Made mistake... the reason the code works when $good_guesses is undefined is that there is a condition in front of the condition... 

elsif ((defined($good_guesses))&&($guess =~ /[$good_guesses]/))

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that prevents the interpretation 
$guess =~ /[]/

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when $good_guesses is not defined

In reply to Re: Resetting variables by Sandy
in thread Resetting variables by yacoubean

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