Re^6: Repeat question (redo)

Hi again. I've been going through your code and it's starting to make sense. However, what is the function DEFINED going.?

Until (defined $input && $input == $answer) {
        print "Sorry that's not right, please try again\n" if defined 
+$input;
[download]

Comment on Re^6: Repeat question (redo) Download Code

Replies are listed 'Best First'.
Re^7: Repeat question (redo) by hippo (Archbishop) on Dec 11, 2018 at 12:05 UTC
It returns true if its argument is defined and false otherwise. See perldoc -f defined. The first time through the loop, `$input` is undefined so we don't want to try to compare it with anything and we equally don't want to warn the user that their guess was wrong when they haven't even entered a guess yet.	[reply] [d/l]