CODEWITHSUNDEEP
regex
Justin808
Justin808

Reputation: 21512

How do I account for all possible orders?

I have 7 items...

a b c d e f and g

The seven items can be in any order. How to I check with regex that they are there (or not) but no other items are...

^(a)?(b)?(c)?(d)?(e)?(f)?(g)?$

Thad would check for the seven items with any combination of items missing, but only in that order. How do I have the regex check for any possible order of the 7 items?

Both of these would pass:

abcdefg
aceg

I need these to pass as well

bc
fabcd
bgef

I'm using single letters to simplify things. For example (\stest)? would be an example of one of the items (\skey="([^"<>]+)?")? is another... I would like to prevent duplicates as well.

These should not pass

abca
aa
gfdef

Upvotes: 0

Views: 77

Answers (2)

Saic Siquot
Saic Siquot

Reputation: 6513

If you are using php use preg_split seven times with a, b, c, d, e, f, g as the spliter expresion.

Concatenate the result and perform the next.

If any split gives you more than 2 elements you have duplicates
if your resulting final string is different from '' you have invalid parts.

Here you have the code

// checks that any part present is valid but not repeated and not extra stuff
function checkAny($que) {
   // atention to the escaping \
   $toCheck = array('a','b','c','\\skey="([^"<>]+)?"','d','/slashtest','f','g');
   
   foreach($toCheck as $one){
      // $t = preg_split('/'.preg_quote($one,'/').'/', $que);  // preg_cuote is not valid for your propouse
      $t = preg_split('~'.$one.'~', $que);                     // so, select a proper sign insted of ~
      if(count($t)>2) return 'fail: repeated component/part';
      $que = implode('', $t);              // can use trim() here if it is usefull for you
      if($que=='')    return 'pass!!!';    //do not waste time doing any more tests
   }
   return 'fail: unknown component/part';
}

//test
echo checkAny('abcc');                 // fail
echo checkAny('ab/slashtestc');        // fail  because the repated a, be careful in test order to avoid this problem
echo checkAny('abcg');                 // pass
echo checkAny('ab key="xx"c');         // pass

if php is not the case, preg_replace can be easy substituded on any language supporting regex

Upvotes: 0

manojlds
manojlds

Reputation: 301147

Something like this would work:

^(?!(.*(a|b|c|d|e|f|g).*(\2)))((a|b|c|d|e|f|g)+)$

Upvotes: 1

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