iterating through a string, choosing a pattern
Pattern matching example from a Well House Consultants training course
More on Pattern matching [link]
Source code: patplode Module: U108
Here are some examples of how you can iterate through a
string collecting the sections that match a particular pattern
print ("\niterating through the words in a string")
stuff = "to iterate through this, we match at ... punctuation!"
for k in string.gmatch(stuff,'%w+') do
print ("\nAlternative - capturing non-spaces")
for k in string.gmatch(stuff,'%S+') do
print ("\nCapture a char, then greedy to last repeat of it")
for k,j,l in string.gmatch(stuff,'(.)(.*)(%1)') do
print ("\nCapture a char, then sparse to last repeat of it")
for k,j,l in string.gmatch(stuff,'(.)(.-)(%1)') do
print ("\n6 chars at a time, 2 to one variable and 4 to another")
for k,j in string.gmatch(stuff,'(..)(....)') do
print ("\niterating through the parameters to a CGI script")
cgistring = 'this=17&that=24&somemore=extra text'
for k3,k4 in string.gmatch(cgistring,'([^=&]+)=([^&]+)') do
--[[ ------------------ Sample output -------------------
[trainee@easterton u108]$ lua patplode
iterating through the words in a string
Alternative - capturing non-spaces
Capture a char, then greedy to last repeat of it
t o iterate through this, we match at ... punctua t
Capture a char, then sparse to last repeat of it
t o i t
e rat e
t his, we ma t
c h at ... pun c
t ua t
6 chars at a time, 2 to one variable and 4 to another
ou gh t
hi s, w
h at .
iterating through the parameters to a CGI script
somemore extra text
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
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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.
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