Lrexlib Hello World?

[rulatir]

What do I do after installing this library (i.e. a particular flavor)? What exactly do I require to obtain the rex object mentioned extensively in the docs? Assuming I managed to obtain this object, do I need to initialize it somehow (e.g. tell it which of the installed flavors to use), or is it somehow ready out of the box (because, hypothetically, only one flavor can be installed at a time)?

These questions may appear silly at first sight, but there really is a gap in the available introductory knowledge. I can find the info on how to compile and install the library. I can find the info about its individual functions in the reference manual. What I can't find info about is how to get from the former to the latter: a simple example of a small self-contained Lua program that imports, configures and uses lrexlib.

[rulatir]

Finding this old discussion:

http://lua-users.org/lists/lua-l/2008-08/msg00060.html

I would like to clarify that I am not requesting an extensive tutorial, just a 15 LOC hello world!

[shmuz]

Here you go:

local rex = require "rex_pcre"
local subj = "We go to school"
local patt = "(\\w+)\\s+(\\w+)"
local repl = "%2 %1"

local from, to, cap1, cap2 = rex.find(subj, patt)
print(from, to, cap1, cap2)

local result = rex.gsub(subj, patt, repl)
print(result)

[shmuz]

What exactly do I require to obtain the rex object mentioned extensively in the docs?

You require() "rex_pcre", "rex_gnu", "rex_onig", etc.

Assuming I managed to obtain this object, do I need to initialize it somehow

No you don't need.

hypothetically, only one flavor can be installed at a time

Usually one flavor is enough but there's nothing wrong in using say "rex_pcre" and "rex_onig" in the same script. It is so because they are in fact 2 different libraries (they share parts of their source code but once they are compiled and linked they are totally independent).

[rulatir]

Thanks! It would be great however if this listing could be added to the readme or to the reference.

[petRUShka]

Thanks for the library! I want to say that issue is very helpful as getting started. And that example is definetely missed in README.