perl exact string match

Question

I have following Perl code to prompt user for yes/no answer. If the user enters anything else than yes/no, keep prompting. No other word is acceptable. I don\'t know why thi

Answer 1

You should use following Perl regular expression for matching only yes or no (case insensitive):

m/^(yes|no)$/i

For yes only, use:

m/^yes$/i