Is there a way to include an if statement in a regular expression, in javascript. This sort of thing:
var regex = /"if followed by [0-9] then match [a-m], else match [n-z]"/i so:
"a9" //returns a match "aa" //doesn't return a match "na" //returns a match I hope this makes sense.
Thanks in advance
You would need this:
([a-m][0-9])|([n-z][a-m]) Or, if that is full of alphabets, then:
([a-m][0-9])|([n-z][a-z]) For the given input, it gives:
MATCH 1 1. `a9` MATCH 2 2. `na` Check online at RegEx 101.
Working
Explanation
The closest equivalent to if in regex is the alternation, |, where the regex will match as far as it can in a branch of the alternation, and try to match the next one(s) if it fails.
To code your exact statement in regex, one would use (?=.[0-9])[a-m]|[n-z] where you use lookahead to check the condition.
However you can use this much simpler regex :
[a-m][0-9]|[n-z] 
