Pattern matching

[KayleMaster]

Here I am again.
I'm kinda new to lua's strings, being a C guy and all, and I don't really know every function, so can you help me?

I have this string: wood|1000
so the pattern is word|digits
First I need to get word and compare it, if it's =="wood" for example and then I need to get the value. How would I do that? I could only get either the word with "%a+" or the value "%d+" but I failed getting both. Maybe because I used gsub, dunno.

EDIT: Ok so I got this now:

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local arg = string.match(string_recv, "%a+") 
if arg == "wood" then wood = string.match(string_recv, "%d+") end

but what if I have wood|1000|stone|2000, how would I handle that?

[Ref]

I'm not too good with pattern matching but what's wrong with:

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str = 'wood|1000'
sep = string.find( str, '|' )
word, value = string.sub( str, 1, sep-1 ), str:sub( sep+1, #str )

or maybe

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word, value = string.match(str, "(%a+)|(%d+)")

[zorg]

but what if I have wood|1000|stone|2000, how would I handle that?

I'd use a different separator for each pair of "key":"value" pairs, makes things simpler. Probably.

[raidho36]

The gsub function makes a substitution. The match function can retrieve matching substrings.

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t, c = string.match(str, '(%a+)\|(%d+)')

What you looking for is regex tutorial, and user manual. Regular expressions are the to go method of text processing. It replaces manually scanning the string for characters using complicated sets of conditions and switches which gets unwieldy very quickly.

[KayleMaster]

I've always wondered how a function can return two values, in this case, to t and c. And I always forget I can do that...

[raidho36]

Lua pushes return values to stack, function call arguments too. So there is no problem accepting and returning any number of values. Unused values are simply dropped, whatever's missing is reported as nil.