By Comparison, UK Postal Codes Offer a Greater Challenge Than US Zip Codes When Writing Regular Expressions (RegEx)
In the previous blog (“Finding US Zip Codes (AutoHotkey RegEx Tips Part 1)“), I began this mini-tutorial series on AutoHotkey Regular Expressions (RegEx) with a technique for parsing US zip codes from street addresses. For the MultiPaste.ahk script to work best (“Parsing and Pasting One-Line Street Addresses (AutoHotkey Multi-Paste Trick)“), I needed any zip code to appear as a separate paste item in the MultiPaste MsgBox. The parsing problem occurs because most one-line address formats only use as a delimiter the space character (no comma or newline) between the state and zip code. The same holds true for UK postal codes.
Last time, I pointed out how the string functions—InStr() and StrReplace()—require exact search characters while the Regular Expressions functions—RegExMatch() and RegExReplace()—can use a variety of wild cards to represent characters. In fact, the various different ways to express wild cards cause a degree of confusion. In this blog, I introduce the \w alphanumeric wild card and the question mark modifier (?) to create optional matches. Continue reading