Re: Yes No Validation

Your regexps are matching anything that starts with 'y' or 'n' (any case). Just expand and anchor the matches to look like this:

if (/^y|yes|n|no$/i)
    {
        if (/^no?$/i) 
            { 
                print "Begone, evil peon!\n"
            } 
        if (/^y(es)?$/i)
            {
                print "YIPPEEE.!!!!\n";
            }
    } else {
        # Validate user input and return message if invalid
    print "\n\n=====================================\n";
        print "You Have Entered and Incorrect Option\n";
        print "Valid Options are [Y/N]\n";
        print "=====================================\n\n";
        &answer;
    }
[download]

Comment on Re: Yes No Validation Download Code

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Re^2: Yes No Validation by LAI (Hermit) on Feb 06, 2003 at 20:52 UTC
That first Regexp will fart. See, the way it's written, it will match either a 'y' at the beginning of the string, a 'yes' or 'n' anywhere in the string, or a 'no' at the end. You need to put parens around the patterns to isolate them from the anchors. Also, I'd prefer an elsif to nested ifs: `if (/^(y\|yes)$/i) { print "YIPPEEE.!!!!\n"; } elsif (/^(n\|no)$/i) { print "Begone, evil peon!\n" } else { # Validate user input and return message if invalid print "\n\n=====================================\n"; print "You Have Entered and Incorrect Option\n"; print "Valid Options are [Y/N]\n"; print "=====================================\n\n"; &answer; }` [download] However, I would much prefer to use a for as a switch case: `SWITCH: for ($input) { /^(y\|yes)$/i && do { print "YIPPEEE.!!!!\n"; last SWITCH; }; /^(n\|no)$/i && do { print "Begone, evil peon!\n"; last SWITCH; }; # Validate user input and return message if invalid print "\n\n=====================================\n"; print "You Have Entered an Incorrect Option\n"; print "Valid Options are [Y/N]\n"; print "=====================================\n\n"; &answer; }` [download] LAI :eof	[reply] [d/l] [select]

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Re^2: Yes No Validation
by LAI (Hermit) on Feb 06, 2003 at 20:52 UTC

That first Regexp will fart. See, the way it's written, it will match either a 'y' at the beginning of the string, a 'yes' or 'n' anywhere in the string, or a 'no' at the end. You need to put parens around the patterns to isolate them from the anchors. Also, I'd prefer an elsif to nested ifs:

if (/^(y|yes)$/i)
    {
        print "YIPPEEE.!!!!\n";
    }
elsif (/^(n|no)$/i) 
    { 
        print "Begone, evil peon!\n"
    } 
else 
    {
    # Validate user input and return message if invalid
    print "\n\n=====================================\n";
    print "You Have Entered and Incorrect Option\n";
    print "Valid Options are [Y/N]\n";
    print "=====================================\n\n";
    &answer;
    }
[download]

However, I would much prefer to use a for as a switch case:

SWITCH: for ($input) {
    /^(y|yes)$/i && do {
        print "YIPPEEE.!!!!\n";
        last SWITCH;
        };
    /^(n|no)$/i && do {
        print "Begone, evil peon!\n";
        last SWITCH;
        };
    # Validate user input and return message if invalid
    print "\n\n=====================================\n";
    print "You Have Entered an Incorrect Option\n";
    print "Valid Options are [Y/N]\n";
    print "=====================================\n\n";
    &answer;
}
[download]

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