Re: Understanding Strings

[Sean Conner <sean@...>]

It was thus said that the Great Mike McGonagle once stated:
> OK, I'm stumped... I have a string...
> 
> "tobj index (0 6 45)"
> 
> how do I parse the string to get the left paren? I am using string.find and
> passing a single character which gets used as a pattern. This works fine
> when passed a "{" or a "<", but it chokes on "(" and "[". I just want to
> convert the enclosed data to a sub-table.
> 
> None of the tutorials I have read seem to touch on writing such patterns.
> If you could lead the way?

  You could try using LPeg.  Here's the code that will parse the data:

	re = require "re"

	G = [[
		parser          <- [^(]+ '(' items+ -> {} ')'
		items           <- %s* {[0-9]+} %s*
	]]
  
	parser = re.compile(G)
	x = parser:match("tobj index (0 6 45)")

	for i = 1 , #x do
	  print(x[i])
	end

  I personally find this a bit easier to read than regular expressions.

  -spc