patterns question - ComputerCraft Forums (archive)

KingofGamesYami #1

3057 posts

Location United States of America

Posted 20 May 2014 - 04:53 AM

Is there any way to make a pattern that expects 0 or more characters? "%a+" accepts 1+, "%a?" accepts 0 or 1. Would I simply combine the two ("%a?+" or "%a+?")? Or would I simply have to make an extra elseif statement?

theoriginalbit #2

7508 posts

Location Australia

Posted 20 May 2014 - 05:21 AM

if you read this link, you'll find that - and * are both 0 or more repetitions, so it would be "%a*" or "%a-"

Edited on 20 May 2014 - 03:22 AM

KingofGamesYami #3

3057 posts

Location United States of America

Posted 20 May 2014 - 05:29 AM

theoriginalbit, on 20 May 2014 - 05:21 AM said:
if you read this link, you'll find that - and * are both 0 or more repetitions, so it would be "%a*" or "%a-"

Thanks… I didn't remember that for some reason. probably because it was around 2 A.M. when I was reading it.

apemanzilla #4

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1610 posts

Posted 20 May 2014 - 04:32 PM

You can use "or" in patterns? O.o

Lignum #5

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570 posts

Posted 20 May 2014 - 04:39 PM

apemanzilla, on 20 May 2014 - 04:32 PM said:
You can use "or" in patterns? O.o

No. In regexes you can do things like "(A|B)" which means "match the letter A or B" but there's nothing like it in Lua patterns sadly.

Edited on 20 May 2014 - 02:39 PM

apemanzilla #6

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1610 posts

Posted 20 May 2014 - 04:59 PM

Lignum, on 20 May 2014 - 04:39 PM said:
apemanzilla, on 20 May 2014 - 04:32 PM said:
You can use "or" in patterns? O.o
No. In regexes you can do things like "(A|B)" which means "match the letter A or B" but there's nothing like it in Lua patterns sadly.

Yes, that's what I thought… The OP used an "or" operand in their capture, so I wasn't sure.

Edited on 20 May 2014 - 02:59 PM

wieselkatze #7

227 posts

Location Germany

Posted 20 May 2014 - 09:42 PM

As far as I know you could just use (for an or) "[AB]" which would result in searching for A or B.

Wojbie #8

724 posts

Location Kinda lost

Posted 20 May 2014 - 10:15 PM

wieselkatze, on 20 May 2014 - 09:42 PM said:
As far as I know you could just use (for an or) "[AB]" which would result in searching for A or B.

yea but thats on character level - you cant code it to look for "cat" or "dog"

KingofGamesYami #9

3057 posts

Location United States of America

Posted 20 May 2014 - 10:29 PM

apemanzilla, on 20 May 2014 - 04:59 PM said:
Lignum, on 20 May 2014 - 04:39 PM said:
-snip-
Yes, that's what I thought… The OP used an "or" operand in their capture, so I wasn't sure.

I was simply stating two different ways of doing what I thought might work…
%a+? and %a?+

my logic:
%a+? would check for multiple characters, but they can be none because the entire statement has ? after it
%a?+ checks for one or more "maybe" space characters
–This is irrelevant I know what I'm using now–