| |||
String Pattern Matching
Pattern matching example from a Well House Consultants training course
More on Pattern matching [link]
Source code: stratch Module: U108
info = "Aylesbury Melksham Melksham Melksham Bristol Bristol Melksham" print ("\nGlobal Substitute") i2 = string.gsub(info,"Melksham",'"Well House Manor"') print (i2) print ("Global Substitute - limited number of replacements") i3 = string.gsub(i2,"\"Well House Manor\"",'MKM',2) print (i3) --[[ Lua uses a pattern matching system that is NOT regular expressions Reason - "Lua is a small, tight language and a POSIX Regular Expression engine would have been bigger than the entire string function library" But is is quite similar ;-) ]] print ("\nBracket classes - any one of") i2 = string.gsub(info,"[aeiou]",'VV') print (i2) print ("\nFind returns the position of the match") i2 = string.find(info,"[aeiou]") print (i2) --[[ ^ means "starting with" $ means "ending with" %d means a digit %a for a letter %u for an upper case letter %l for a lower case letter %% means really match a % character (similar for other specials) + means one or more of the previous item ? means zero or 0ne character * means 0 or more or the previous item - also means 0 or more of the previous item but is SPARSE ]] --[[ ----------------- Sample Output [trainee@easterton u108]$ lua stratch Global Substitute Aylesbury "Well House Manor" "Well House Manor" "Well House Manor" Bristol Bristol "Well House Manor" Global Substitute - limited number of replacements Aylesbury MKM MKM "Well House Manor" Bristol Bristol "Well House Manor" Bracket classes - any one of AylVVsbVVry MVVlkshVVm MVVlkshVVm MVVlkshVVm BrVVstVVl BrVVstVVl MVVlkshVVm Find returns the position of the match 4 [trainee@easterton u108]$ ]] Learn about this subject
This module and example are covered on the following public courses:
* Learning to program in Lua * Lua Programming * Lua Programming Also available on on site courses for larger groups Books covering this topic
Yes. We have over 700 books in our library. Books
covering Lua are listed here and when you've selected a
relevant book we'll link you on to Amazon to order.
Other Examples
This example comes from our "Pattern matching" training module. You'll find a description of the topic and some
other closely related examples on the "Pattern matching" module index page.
Full description of the source code
You can learn more about this example on the training courses listed on this page,
on which you'll be given a full set of training notes.
Many other training modules are available for download (for limited use) from our download centre under an Open Training Notes License. Other resources
• Our Solutions centre provides a number of longer technical articles.
• Our Opentalk forum archive provides a question and answer centre. • The Horse's mouth provides a daily tip or thought. • Further resources are available via the resources centre. • All of these resources can be searched through through our search engine • And there's a global index here. Web site author
Purpose of this website
This is a sample program, class demonstration or answer from a
training course. It's main purpose
is to provide an after-course service to customers who have attended our
public private or
on site courses, but the examples are made
generally available under conditions described below.
Conditions of use
Past attendees on our training courses are welcome to use individual
examples in the course of their programming, but must check
the examples they use to ensure that they are suitable for their
job. Remember that some of our examples show you how not to do
things - check in your notes. Well House Consultants take no responsibility
for the suitability of these example programs to customer's needs.
This program is copyright Well House Consultants Ltd. You are forbidden from using it for running your own training courses without our prior written permission. See our page on courseware provision for more details. Any of our images within this code may NOT be reused on a public URL without our prior permission. For Bona Fide personal use, we will often grant you permission provided that you provide a link back. Commercial use on a website will incur a license fee for each image used - details on request. | |||
PH: 01144 1225 708225 • EMAIL: info@wellho.net • WEB: http://www.wellho.net • SKYPE: wellho PAGE: http://www.wellho.net/resources/ex.php4 • PAGE BUILT: Sun Oct 11 14:50:09 2020 • BUILD SYSTEM: JelliaJamb |