Negate characters in Regular Expression

Question

How would I write a regular expression that matches the following criteria?

• No numbers
• No special characters
• No spaces

in a st

Answer 1

In Perl, it would be something like:

$string !~ /[\d \W]/

Of course, it depends on your definition of "special characters". \W matches all non-word characters. A word character is any alphanumeric character plus the space character.