Sams Teach Yourself Perl in 21 Days, Second Edition

Q&A

Q1:	I want to iterate over a string and count the occurrences of the letter t. How can I do this in Perl?
A1:	Well, you could use a for loop and one of the string functions to work your way through the string one character at a time, but that would be a terrible amount of overkill (and expose you as a C programmer who still thinks of strings as null- terminated arrays). Perl's good with strings, and it has built-in mechanisms for finding stuff in strings so you don't have to do perverse character-by-character comparisons. You'll learn more about this sort of pattern matching on. Don't spend a lot of time iterating over strings until you read that.
Q2:	I don't understand why in these scripts you are testing for nonnumeric data using \D, when ...