Re: [NTG-context] Regular expressions in Lua.

15 Dec 2012


      On 12/15/2012 1:12 AM, Andre Caldas wrote:
...
Hi!
I have to use pattern matching in lua. I tried the function "string.gmatch".
I want to match (iterate over) strings of the type
([0-9]+)(-([0-9]*))?(,|$)
...
For example:
1,3- (iterations: 1 and 3-)
1-3,6,7 (iterations: 1-3 then 6 then 7)
1-2,5-6,10- (iterations 1-2 then 5-6 then 10-)
function whatever(str,n,action)
     action = action or print
     for s in string.gmatch(str,"[^,]+") do
         local a, b, c = string.match(s,"^(%d+)(%-?)(%d-)$")
         if c ~= "" then
             for i=tonumber(a),tonumber(c) do
                 action(i)
             end
         elseif b ~= "" then
             for i=tonumber(a),n or tonumber(a) do
                 action(i)
             end
         elseif a then
             action(tonumber(a))
         end
     end
end

whatever("1,3-",5,function(i) print(">>>",i) end)
whatever("1-3,6,7")
whatever("1-2,5-6,10-",30)


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