15. Metacharacters - Dot

• Yes, the humble dot just happens to be regex shorthand for "any character". (Well, almost... In some tools the dot will not match on a null and/or something else - we'll get there soon!)
• Say we wanted to search some files for a phone number, 08 1234 5678.
• The only problem is, we're not sure if the phone number has been written as "08 1234 5678", or "08 1234-5678" or even "(08)1234 5678".
• Fortunately, dot comes to the rescue!

    08.1234.5678
          

  will match any of those phone numbers!
• Okay, the same regex will also match something like "08/1234%5678" or "088123405678" which we don't want. So, we could have used the regex:

    08[ )]1234[ -]5678
          

  to match any of the three examples above.
• That second regex isn't very easy to read though, and it's pretty specific - it won't match the phone number if it happened to be written as "08-1234-5678".
• So, as mentioned before, regexes are a balance between matching what we do want vs. not matching what we don't - and a lot of the time, knowing a little bit about the data we are searching with our regex will help us to decide on how best to "phrase" our regular expression.